**3. Effectiveness of agricultural zoning**

Researchers have developed several techniques and models to capture the impact of agricultural zoning on land-use change. These techniques can be grouped into two main approaches which are the pricing approach and the outcome approach. The pricing approach is the way which researchers use market prices as a proxy for effects on land use as land price reflects the conversion potential of the zoning policy that embodies in the parcel. While the outcome approach focuses on observing the physical land-use change comparing to the use before the implementation of the policy.

Pricing approach has several features. One popular feature of pricing approach is based on the land rent theories of Von Thunen and Ricardo. Given respective attributes and location, any parcel of land can be modeled for use in a way that would earn the highest rent. A number of studies have attempted to estimate the extent to which support policies have increased farmland prices, but I found only one that examines the effect of zoning policy on farmland price which is the work of [9]. The work found that large lot zoning, total acreage, distance from a highway, distance from a town, and the presence of a house on the parcel are the determinants of the price per acre of farmland. In addition, weighted productivity index and greater soil value were found to be negatively correlated with land prices. Another popular feature of pricing approach is based on the concept of local government that tries to maximize profit through zoning policy. Zoning is a function of land attributes and land price. Land prices are also a function of parcel characteristics and the designed zoning. If zoning policy is effective, the method should produce an effect on land price. Many works examine the effect of the zoning on land price based on this concept. Vaillancourt and Monty [10] found that the land zoned for agriculture is 15–30% less in price than unrestricted land. Wallace [11] also found that zoning policy decreases the price of parcel zoned for large lots and the land price is found to be higher for other type of zoning. Logan and Zhou [12] indicated that zoning has modest effect on the changes in land rent, local population, family income, and the number of black population. The agricultural landowners perceive that the limitations imposed on their permitted uses will decrease their land value, but it is not always be the case. McMillen and McDonald [13] analyzed the correlation between zoning policy and land use, finding policy to have a strong effect on land utilization. Henneberry and Barrows [14] indicated that the effect of agricultural zoning on land price depends on the location and characteristics of the parcel. The agricultural zoned parcel that is located far from the city center is found to have a higher price than the agricultural zoned parcels close to the city. The result is in line with [15] who found that the land zoned for low-density development has a significant decrease in value, while the land zoned for high density or for community has a significant increase in value. More recent work of [16] also showed that agricultural zoning can be an effective policy for protecting productive farmland, while in the evidence from Japan, Nishihara [17] showed that agricultural land zoning policy has a great impact on land value increase and discourages the landowner from cultivating the land. A small gap in the anticipation of land policy to convert agricultural zone to residential development zone prevents landowner from selling or leasing the land to a more efficient farmer. Some studies based on this concept indicated that the zoning policy is not an effective tool for managing land use. Mark and Goldberg [18] examined the relationship between rezoning and changes in property values and the ability of zoning to mitigate externalities and found that rezoning does not necessarily lead to changes in land use and value. In the evidence from the United States, Pogodzinski and Sass [19] showed that zoning has no effect on house price but instead the minimum lot sizes, minimum side yard restriction, and maximum height restrictions affect house price, suggesting that the zoning method does not affect land use.

nuance and idea of the event and helps to answer the questions: where have we come from,

The secondary sources which include historical literatures in agricultural zoning, research papers, Thailand agricultural acts, government office reports, and online news were used as a tool to gain an experiential sense of the past and provide policy design resource. In the previous section, the review of general application of agricultural zoning program reveals that the method is actually one of the kinds of property rights, and the general objectives to apply the agricultural zoning of a country are to preserve the agricultural area and ensure food security. In the next section, the review of agricultural zoning performance paper in various countries will be discussed. This step helped to establish a background of the historical analysis into the

Researchers have developed several techniques and models to capture the impact of agricultural zoning on land-use change. These techniques can be grouped into two main approaches which are the pricing approach and the outcome approach. The pricing approach is the way which researchers use market prices as a proxy for effects on land use as land price reflects the conversion potential of the zoning policy that embodies in the parcel. While the outcome approach focuses on observing the physical land-use change comparing to the use before the

Pricing approach has several features. One popular feature of pricing approach is based on the land rent theories of Von Thunen and Ricardo. Given respective attributes and location, any parcel of land can be modeled for use in a way that would earn the highest rent. A number of studies have attempted to estimate the extent to which support policies have increased farmland prices, but I found only one that examines the effect of zoning policy on farmland price which is the work of [9]. The work found that large lot zoning, total acreage, distance from a highway, distance from a town, and the presence of a house on the parcel are the determinants of the price per acre of farmland. In addition, weighted productivity index and greater soil value were found to be negatively correlated with land prices. Another popular feature of pricing approach is based on the concept of local government that tries to maximize profit through zoning policy. Zoning is a function of land attributes and land price. Land prices are also a function of parcel characteristics and the designed zoning. If zoning policy is effective, the method should produce an effect on land price. Many works examine the effect of the zoning on land price based on this concept. Vaillancourt and Monty [10] found that the land zoned for agriculture is 15–30% less in price than unrestricted land. Wallace [11] also found that zoning policy decreases the price of parcel zoned for large lots and the land price is found to be higher for other type of zoning. Logan and Zhou [12] indicated that zoning has modest effect on the changes in land rent, local population, family income, and the number of black population. The agricultural landowners perceive that the limitations imposed on their permitted uses will decrease their land value, but it is not always be the case. McMillen and McDonald [13] analyzed the correlation between zoning policy and land use, finding policy to have a strong effect on land utilization. Henneberry

where are we now, and where are we going? [8].

56 Land Use - Assessing the Past, Envisioning the Future

**3. Effectiveness of agricultural zoning**

policy design process.

implementation of the policy.

The other approach that uses to evaluate the effectiveness of zoning measure is the outcome approach. The approach is a direct proxy on land-use change as it compares the real physical change before and after the implementation of the policy. Not much research has been done on this approach. In England, Coughlin [20] found that agricultural zoning significantly reduces the sales of farmland to the conversion purpose, while in the evidence from the United States, Kline and Alig [21] found that the zoning reduces the likelihood of development on the land located within forest use, but the result for exclusive farm use zones is inconclusive. Levine [22] examines the effect of the growth-control enactment between 1979 and 1988 on net housing construction between 1980 and 1990. The study showed that local growth-management measures significantly displaced new construction such as rental housing and an expansion of the metropolitan areas into the interiors of the state. The measures have strong impact on low-income households and minorities, but not all growth-control measures were associated with this change, and the strong effect was found in the zoning measure. Cho and Wu [23] also adopts this concept to evaluate the interactions between residential development, land-use regulations, and public financial impacts in California, Idaho, Nevada, Oregon, and Washington. The study found that the land-use regulation decreases land development, longrun expenditure and property tax at the higher cost of housing prices, and property tax, while land-use regulations, land development, public expenditure, and property tax are affected by population, geographic location, land quality, housing prices, and the risks and costs of development. Mayer and Somerville [24] found that land-use regulation lowers the steady-state level of new construction. Metropolitan areas with more extensive regulations have up to 45% fewer starts and price elasticities that are more than 20% lower than those in less regulated markets. Kuminoff and Sumner [25] found that population growth and edge length of urban interface are statistically significant and positively correlated with conversion. Zoning and development restrictions were not significant explanatory variables for conversion. More strong result was found in the work of [26]. They evaluated the efforts of Utah County to discourage the farmland conversion to other uses and found that zoning has not been successful in agricultural land protection. Coxhead and Demeke [27] evaluated the determinants of land-use decisions made by farmers in an upland area of the Philippines. According to the findings, the most important predictors explaining substantial farmland allocations were crop prices and policy reform.

The past evidence and studies do not provide any conclusion, that is, if the agricultural zoning policy is actually helpful to protect agricultural land and ensure the food sustainability. The only best conclusion that can be drawn from these researches is that the performance of zoning policy depends on the circumstance and the context of each government. One must be tempted to think that the government that has similar context and circumstance will be able to refer to the research result of each other as a guideline for managing their land use, but in reality there is no absolute likeness in a context and circumstance of government. The agricultural zoning formulation of a country is, in fact, a complex issue. Therefore, there is a need for evaluating each government policy performance separately in order to improve and solve an individual measure while the policy is on process.
