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以水分平衡原理为基础,运用系统分析手段,结合黄土高原的自然特点,提出了林木耗水研究新方法——“单株平衡定期测定法”,建立了单株水分平衡计算方程。有效地实现了林木蒸腾耗水与林地蒸发量的分别测定。并以此对黄土高原主要造林树种油松、刺槐及主要经济林树种苹果、梨、杏树,进行了生长季耗水量测定。结果表明,黄土高原林木蒸腾量,主要受土壤水分供给条件的制约,年际间随降雨量变化而增减,差异较大。反映了水分作为该区林木生长限制因子的重要作用。经测定、分析,提出了黄土高原林地土壤水分潜势的“利用创造性”理论,并指出了土壤水分“用则生,弃则失,不积累,可提高”的属性；提出并建立了“水分潜势方程“WP=△E+△O-I”。给出了运用“单株平衡定期测定法”，进行土壤水分生产力计算的“水分潜势计算方程“WP=Ps+△Wf_2-Of”，并求得了不同树种各立地水分潜势值。根据单株生物量增长值及所耗水量，求得了不同立地各树种蒸腾效率，结合水分潜势，进一步求得了不同树种各立地期望最大生产力。提出了“需水一潜势代换法”，实现了同一立地多树种蓄积量代换评价。根据径流林业思想，提出并建立了“集流一潜势”关系方程A/B=(WPs-WPa)/(P·Osp)，实现了径流林业生产力的理论计算n棵出了黄十高厦治理与?
Based on the principle of water balance, a new method of study on water consumption of forest - “Periodic equilibrium method of single plant” was put forward by means of systematic analysis and combined with the natural characteristics of the Loess Plateau. The calculation equation of water balance was established. Effectively achieved the forest transpiration water consumption and forest evaporation were measured separately. Based on this, the water consumption of growing season was measured on Pinus tabulaeformis, Robinia pseudoacacia and the main economic tree species of apple, pear and almond in the afforestation trees of the Loess Plateau. The results showed that the transpiration amount of forest in the Loess Plateau was mainly controlled by the soil water supply conditions, and varied with the change of rainfall during the year, which was quite different. It reflects the important role of moisture as a limiting factor for forest growth in this area. The theory of “using creativity” of soil moisture potential in forestland on the Loess Plateau was determined and analyzed, and the attribute of “utilization and creativity” of soil moisture was pointed out. It was pointed out that “ Potential equation ”WP = △ E + △ OI“ is given. ”Water potential calculation equation“ WP = Ps + △ Wf_2-Of ”is calculated using the“ single plant equilibrium regular determination method ” Different species of each site moisture potential value. According to the biomass growth value and water consumption, the transpiration efficiency of each tree species in different habitats was obtained. Based on the potential of water potential, the maximum productivity of each tree species in different sites was obtained. Put forward the “water demand for a potential substitution method” to achieve the same site multiple stock substitution evaluation. According to the idea of runoff forestry, a relational equation of “current-flow potential” A / B = (WPs-WPa) / (P · Osp) was proposed and established to realize the theoretical calculation of runoff forestry productivity. Governance and?