What are the economic, social and ecological indicators to measure the intensive use of land?

plot ratio: the ratio of the total construction area within the project land area to the total land area of the project. Calculation formula: floor area ratio = total construction area ÷ total land area When the height of a building exceeds 8m, the floor area of this floor will be doubled when calculating the floor area ratio. The lower the floor area ratio, the higher the comfort of residents, and vice versa. The so-called "floor area ratio" refers to the ratio of the total construction area to the land area of a community. For developers, the plot ratio determines the proportion of land cost in housing, while for residents, the plot ratio directly relates to the comfort of living. So is the greening rate. The greening rate is higher, the floor area ratio is lower, and the building density is generally lower. The less area developers can use to recover funds, the more comfortable residents will be. These two ratios determine whether the project designs a community from the perspective of people's living needs or from the perspective of purely making money. In a good residential area, the plot ratio of high-rise residential buildings should not exceed 5, that of multi-storey residential buildings should not exceed 3, and the greening rate should not be less than 3%. However, due to the limitation of land cost, not all projects can be done. I. Connotation and characteristics of plot ratio The plot ratio refers to the ratio of the total construction area of houses to the parcel area in a certain plot of urban planning area, which can be divided into actual plot ratio and planned plot ratio. The plot ratio usually refers to the planned plot ratio, that is, the ratio of the total construction area allowed by the planning within the parcel to the parcel area. The floor area ratio reflects the intensity of land use and its utilization benefit, and also reflects the difference of land price level. Therefore, the floor area ratio is an important index adopted in the management of urban zoning, and it is also the most important factor that affects land prices from a micro perspective. The plot ratio has the following characteristics: (1) The plot ratio expresses the allowable building capacity per unit land area in a specific "parcel". Parcel is the basic unit of cadastral management. It is a piece of land with definite boundaries and ownership on the earth's surface, and its area does not include public roads, public green spaces, large-scale municipal and public facilities. The plot ratio can only reflect the specific intensity of land use if it refers to the plot ratio of "parcels", and it is comparable between parcels. (2) There is a certain relationship between floor area ratio (R), building density (C) and number of floors (H). Building density refers to the ratio of building basement area to parcel area in a specific "parcel". When the number of floors of each house in the parcel is the same, and the building area of each floor is the same for a single house, the relationship among them can be expressed as: r = c h, in this case, the number of building floors is in direct proportion to the floor area ratio. (3) The floor area ratio can measure the land price level more accurately. The purpose of people buying land use right is to develop land and build houses. Unilateral development cost of house = unilateral building cost+floor price+tax+floor price = total parcel price/total allowable construction area in parcel = unit price of land/plot ratio. Therefore, floor price can more accurately reflect the level of land price than unit price. (D) The plot ratio has the most reasonable value objectively. In general, increasing the floor area ratio can improve the land use efficiency, but the increase of building capacity will lead to the deterioration of the building environment and reduce the comfort of use. In order to coordinate economic benefits, social benefits and environmental benefits, the plot ratio in urban planning has the most reasonable value objectively. Second, the impact of plot ratio on land price There are many factors that affect land price. Although each factor has different ways to influence land price, its mechanism can be abstractly summarized into two aspects: one is to influence land price by influencing land income, and the other is to influence land price by influencing the relationship between land supply and demand. The income mechanism largely determines the economic surplus of land supply, and the relationship between market supply and demand makes the land price fluctuate relative to the economic surplus, which determines the distribution of the economic surplus of land supply and complicates the change of land price. The influence of plot ratio on land price is influenced by income mechanism and market supply and demand. Generally speaking, the better the location conditions, the higher the land price level, the more prominent the contradiction between supply and demand, and the stricter the land planning control, the greater the influence of plot ratio on land price. Specific performance in the following aspects: (-) Follow the "law of increasing and decreasing returns". Under certain technical and economic conditions, the net income of land will show the characteristics of increasing to decreasing with the increase of land investment. As an urban construction land, the law of increasing and decreasing returns of plot ratio to land price is as follows: when the building density is constant, the increase of plot ratio mainly causes the increase of building floors, and with the increase of building floors, the unilateral cost decreases at the beginning due to the allocation of basic engineering fees and foundation treatment fees; When the number of floors reaches a certain value, it is necessary to strengthen the foundation, increase elevators, strengthen earthquake resistance, etc., and the unilateral cost changes from decline to increase, while the unilateral selling price shows a decreasing trend due to the decline of the quality of the building environment caused by the increase of building capacity. When the unilateral selling price is equal to the unilateral cost, the land revenue reaches the maximum and the land price reaches the highest. At this time, the plot ratio is the most economical plot ratio. If the plot ratio continues to increase, the land investment income will begin to decline because the unilateral selling price is lower than the unilateral cost, and the land price will also begin to decline. For example (Figure 1), MC is the unilateral cost and MR is the unilateral selling price. The land price at a certain plot ratio L is the total income (DCGF area) under the plot ratio minus the normal profits of investors' capital and labor, and the rest is the land price. When the plot ratio is equal to m, the unilateral cost is equal to the unilateral selling price, the marginal income of land development is , the total income (DCNF area) reaches the maximum, the land price reaches the highest, and m is the best plot ratio. Above this plot ratio, the land price begins to change in the opposite direction, and decreases with the increase of plot ratio. (2) The effect of plot ratio on land price is positively related to the city size. First of all, the scale of the city is large, the degree of intensive land use is high, the overall level of land price is high, and the floor land price accounts for a high proportion of the unilateral development cost of the house. The effect of reducing the unilateral development cost of the house by reducing the floor land price is obvious, while the degree of intensive land use is low and the overall level of land price is low in small cities. The unilateral cost of housing development is mainly affected by the unilateral cost of the house. The effect of reducing the unilateral cost of housing development by reducing the floor land price is not obvious, and if the number of floors of the house reaches a certain value, the cost of the unilateral project will increase. In addition, large cities have relatively systematic urban planning data, and land development is strictly controlled by planning, while planning control in small cities is generally not strict, and the determination of plot ratio is often arbitrary. In many places, there is no limit on plot ratio, or there is, but the control is not strict. Moreover, some local governments often encourage buildings to develop into the air in order to establish the image of the city. The higher the better, the plot ratio lacks practical significance in these small towns. Therefore, the larger the city scale, the more obvious the impact of plot ratio on land price, and the greater the change of land price with plot ratio. (3) The floor area ratio has different effects on the land price of different locations in the same city. The urban center has superior location conditions, and its land use intensity, land use benefit, land demand, land scarcity and planning control are higher than those in other regions, especially in urban fringe areas. The fierce competition of investors makes the range of land price change with plot ratio keep or approach the law of land price change with plot ratio under the action of land revenue mechanism. In other areas, with the decrease of land use income, land demand and its scarcity, the effect of plot ratio on land price decreases. Therefore, the influence of plot ratio on land price in the same city is gradually weakened from the center to the periphery. (D) The floor area ratio has different effects on the land price of different types of land. Commercial land is the most sensitive to location conditions, and can only be distributed in a few areas along the road with superior location conditions. The scarcity of land and the contradiction between supply and demand are more prominent than those of residential and industrial land, which is easy to form a seller's market. The economic surplus generated by the increase of plot ratio due to the competition of many land users is mainly expressed in the form of land price and belongs to the land owner. The sensitivity of residential land to location conditions is weaker than commercial use, but stronger than industrial land; Industrial land is generally distributed in the periphery of the city, which is not only the least sensitive to the location conditions, but also restricted by the process flow, and in many cases there is no limit on the floor area ratio. Therefore, in the same city, the influence of plot ratio on different types of land prices is from strong to weak, followed by commercial, residential and industrial land.