Research On Heihe River Basin Land Resources Carrying Capacity Based On Agricultural Ecology Zone Model

Heihe River Basin as the second inland river basin in Northw-est China is not only the largest inland river basin in the west of Gansuand Mongolia,but also the important commodity grain,vegetable and seed pro-duction base in the western region.So,it has an very important strategic positi-on.In recent years,with the rapid growth of population and unreasonable useof water and land, the contradictions of population, resources, environment areprominent,and become one of the important problems that affect the riverbasin sustainable development.The land resources carrying capacity reflects thepopulation carrying capacity of the land resources,so it can visually reflectthe intensity degree of contradictions of population, resources, environment,and have an important reference significance to decision making.So this paperselect the land resources carrying capacity of the Heihe River Basin as themain contents of this article．This paper applies international widely used AEZ model to calculate thephotosynthetic potential productivity, Light and Temperature Potential Producti-vity,Light,Temperature and Moisture Potential Productivity, Light,TemperatureMoisture and Soil Potential Productivity and Agricultural Potential Productivityof the major food crops in Heihe River Basin, and form the land productivitypotential in1km×1km spatial resolution and estimate the land resources carry-ing capacity based on per capita consumption of energy and protein. Then,usi-ng population pressure index to analyse and evaluate the result, and discussthe main influencing factors of the land resources carrying capacity.At last,combining actual conditions of the Heihe River Basin giving some advices toimprove the land resources carrying capacity.The results show that the population densitys of the Heihe River Basincarrying capacity are15.14and13.77per square kilometer calculated by percapita consumption of energy and protein,and it is greater than the populationdensitys of arid area that made by the United Nations,but less than the popu-lation densitys of semi-arid area,and it is very unevenly distributed. the mid-dle part of the heihe river basin can carry about95percent the total populat-ion,the upstream and downstream can only carry5percent the population, but their area is two-thirds of the total area.the population pressure index ofthe Heihe River Basin exceeds the suitable critical value of0.03, the landresources carrying capacity is in the suitable condition.But to each administrat-ive district, the situations are different,the population pressure indexs of EjinBanner, Jinta County, Jiayuguan City, Sunan Yugur Autonomous County and Qilian County are far greater than1.10,belong to overload area, the areas like Jiayuguan city is Serious overload. Linze County, Shandan County and Minle County are in the suitable condition.The population pressure indexs of Suzhou District, Gaotai County and Ganzhou District are less than0.95,So theycan accommodate more people.This paper analyses the influencing factors of the land resources carryingcapacity of the Heihe River Basin viewed from the influence of land productionpotential, finding that for the whole basin,solar radiation is the basic influencefactor, moisture is the main limiting factor, the influence of temperature is next tomoisture,soil effect is relatively small, appropriate economic investment of societycan improve the land resources carrying capacity. To each administrative district, thesituations are different. For Qilian County, the basic influence factor is solarradiation, the main limiting factor is temperature, moisture is next to temperature, theinfluence of soil is not obvious, economic investment of society is an importantmeasure to increase production.But for Ejin Banner, Jiayuguan City, Sunan YugurAutonomous County, Linze County, Shandan County, Minle County, Jinta County,Suzhou District, Gaotai County and Ganzhou District,the basic production potentialis determined by the solar radiation, the main limiting factor is moisture, temperatureis after moisture,the influence of the soil is minimal, economic investment of societygreatly improves the land production potential. According to these influencefactors and the real situation of the Heihe River Basin,finding that improving theland production potential, optimizing the industrial structure and continuing topromote structural adjustment, enhancing the industrialization level and promotingthe new industrialization process are effective measures to alleviate the populationpressure of the Heihe River Basin.