白泥山造林绿化技术研究

历时12 a试验研究,结果表明：在白泥土壤这一特殊立地上进行造林绿化时,桤木、大叶女贞、水杉、池杉、香樟、扁柏等较为适生。其中,桤木表现优为速生,11年生平均树高12.7 m,平均胸径15.9 cm,单株立木平均材积0.121 m3,具较高的生态效益和经济效益。试验同时表明：白泥土壤立地造林的主要关键技术是在选择适应性强树种的同时,采取在造林地开排水沟、大穴整地、客土栽植、及时抚育管理等配套技术措施,其造林成活率比常规技术造林提高30%～50%。     

广东省国有林场营造林项目的问题和对策探讨

2016-2020年广东省国有林场实施了一系列营造林项目,这些项目都取得了不错的效果,但也存在一些问题。文章从项目前期准备方面、项目施工方面、项目实施效果方面提出了相关问题,并针对这些问题,探讨了相关对策。     

Rehabilitation of alkaline wasteland on the gangetic alluvial plains of Uttar Pradesh,India, through afforestation

A few species of fuelwood trees were established on highly alkaline wasteland at Aligarh (27°5′ N., 78°4′ E.) in a tropical environment. Of these Prosopis juliflora produced maximum biomass (12.05 t ha⁻¹) and had an energy content of 242.11 GJ ha⁻¹ after 3.5 years growth period. The survival percentage of Terminalia arjuna was highest of those the species tried, but their growth and biomass production were inferior to that of Prosopis juliflora and Acacia nilotica. Some of the fuelwood tree plantations were raised without adding any soil amendment but suffered heavy mortality and could not produce any significant quantity of biomass. In another experiment Leucaena leucocephala was identified as a most promising species for afforestation on substandard soils; also it was found that a relatively high population density (of about 7,500 plants per hectare) is required to rehabilitate such land. Of the soil amendments tried, gypsum with farmyard manure and sand in equal proportion gave the better response (gypsum alone was also tried). Two species of shrubs: Sesbania sesban and Tamarix dioca have shown good adaptability in difficult habitats. After five years of afforestation the soil properties of the sites improved significantly, showing marked reduction in pH, EC and ESP values and an increase in organic carbon content.