Abstract: Based on an exploratory land use study methodology derived by Dutch scientists, an interdisciplinary research approach has been developed for the analysis and assessment of alternative land use scenarios at County level in consideration of various agricultural constraints for sustainable land use in this paper. A case study on analysis of sustainable land use scenarios was conducted at Quzhou County, Hebei Province. The input-output coefficients for different land use systems at different defined technological levels and at current condition were derived from the farm survey data and the experiment data at Quzhou County. With the linear programming model, in which the net income maximization was the objective function, subject to the land and water resources, possible practice and other economic and biophysical constraints, the different land use scenarios were formulated. Thought comparing of different scenarios, the main results were as following：
(1) Land use structure at different land use scenarios is different. Area of crops is different at different scenarios. For example, area of wheat and maize at organic scenario is the largest, and it is the smallest at sustainable water scenario. For cotton, the smallest area is zero at organic scenario. For spring cotton, the highest area is 110 km² at water scenarios, and the smallest area is zero at organic scenario and pesticide scenario. For vegetable, the area is lower at each scenario because vegetables need more water, the lowest is 22.6 km² at sustainable scenarios. For other crops like bean, rice, peanut and orchard etc, it is area is close or similar at different scenarios. (2) The current practice has the highest economic benefit which is 553.82 million yuan, but it's land use only pay attention to economic benefit and neglect ecological-environmental benefit, this kind of land use would lead to resource degeneration, environmental pollution and so on, it is land use would not be sustainable. All the alternative practices have lower economic benefit than the current practices, but higher than the sustainable practices. These land use consider only one sustainable factor and ignore other factors, thus would not enable sustainable land use eventually for the reason of excessive use of resource. The sustainable practice, which integrated the alternative practices, considered the social, environmental and economic benefits in accordance would be a feasible choice for sustainable land use in future, but it has the lowest economic benefit, which is 361.13 million yuan. The method this paper used intended to generate information for decision support in strategic land use planning by exploring land use options.

Key words: land use system, linear programming, sustainable land use scenarios