装修与电气

本文着重地论述了由装修而引发的电气安全技术问题已到了不容忽视的程度。就此问题作 者提出了自己的观点及解决办法。     

Seed survival and predation of Anoda cristata in soyabean crops

Anoda cristata is a troublesome annual broad-leaved weed in summer crops in the rolling Pampa in Argentina; seeds are the only source of regeneration of this species. Seed persistence or depletion is the result of survival and loss processes, including predation. The objective of this study was to determine survival at two burial depths in undisturbed soil and predation rates of A. cristata seeds in soyabean crops in different rotations and tillage systems. Survival was discontinuous and decreased to 25% after 35 months, after which no further reduction in survival was observed to the end of the experiment at 96 months. No differences in seed survival between seeds placed on the soil surface and buried 5 cm below the soil surface were found at 80 months, but at later times survival was lower for seeds placed on the soil surface. Predation rates ranged between 0.3% day⁻¹ and 6.7% day⁻¹. Of the models tested, a polynomial regression of the rate of predation with time gave the best representation of seed predation. From January to July, predation was higher in non-tillage plots in the wheat/soyabean rotation. There was no significant difference in predation rates between tillage systems in the soyabean monoculture and no difference between planting densities. Higher crop residue levels in non-tillage plots in the wheat/soyabean rotation was the dominant factor influencing seed predation, probably because such habitat favours the presence of seed predators.     

坚持“以林为主”拉动农村经济发展的思考

本文结合集安市市情，提出拉动农村经济发展要坚持以林为主的基本思路。     

退耕还林间作万寿菊的高产栽培技术

本文介绍了万寿菊的形态特征及生物学特性,根据形态特征及生物学特性,探索了万寿菊的育苗技术和栽培技术以及田间管理的方法。     

用生态经济沟的经验建设生态经济岗

本文总结了太行山区过去几十年林业生产的教训,把近几年的“生态经济沟”经验,应用到太行山南部低海拔岗坡地形区的开发治理中,提出了建设“生态经济岗”的设想及盘龙岗试点的规划方案。     

基于图形旋转系统的渐进网格研究

拓扑简化可以为渐进网格带来更好的效果，但目前几乎所有的渐进网格方法都不支持拓扑简化，而且edge collapse和vertex split操作有时会产生非流形．针对这些问题，提出了基于图形旋转系统的渐进网格法．以基于图形旋转系统的数据结构和操作实现了渐进网格，用图形旋转系统的操作集合构建了edge collapse和vertex split操作．在此基础上，通过扩展新操作即可进行任意拓扑变化，从而实现拓扑简化，     

贵州省林业行政案件发生的主要原因分析及对策探讨

对贵州省“十五”林业行政案件发生的原因进行了认真分析,并就进一步加强和改进森林资源保护管理及林业行政执法工作进行了初步探讨。     

Demography of Abutilon theoprasti and Setaria faberi in three crop rotation systems

Field experiments were conducted to characterize the demography of Abutilon theophrasti and Setaria faberi in a conventionally managed 2‐year (maize/soya bean) rotation, and in 3‐year (maize/soya bean/triticale + red clover) and 4‐year (maize/soya bean/triticale + lucerne/lucerne) rotations managed with 72% and 79% lower herbicide inputs respectively. Rates of weed seedling recruitment, seedling survival and adult plant fecundity were determined for populations in each phase of each rotation and used to calculate annual rates of weed population change, Δ. In both years of the study, Δ for A. theophrasti populations declined or remained stable in all three rotation systems. Despite greater rates of seedling survival and fecundity in maize and soya bean in the 3‐ and 4‐year rotations, increases in Δ for A. theophrasti populations were prevented in these systems because of low fecundity in triticale and low seedling survival and fecundity in lucerne. For Setaria faberi populations, Δ remained stable in the 2‐year rotation, increased in the 3‐year rotation in both years, and increased in the 4‐year rotation in 1 year. The results of this study indicate that when herbicide use is reduced, rotations that include triticale and lucerne can facilitate the suppression of A. theophrasti. Rotations that include lucerne can contribute to restraining S. faberi population growth, given adequate levels of seedling mortality in this crop.     

非公有制林业主体融资问题的思考

针对不同层次的个体林业,设计了民间融资、"报账制"式银行信贷等方式以求解决个体林农融资困难问题.     

论塞罕坝森林－草原交错带林业发展策略

在分析塞罕坝林场基本情况、存在问题及优势条件的前提下，提出了该场的林业发展策略：以林为本，林以育为主，育以科学为基础；育林、护林、造林、改造和调整相结合；以木材生产为龙头，以森林旅游和多种经营为双翼，以山草盆花生产及森林食品开发为凤尾，林、工、商、贸综合发展。文中就森林经营、木材加工、森林旅游、植物资源开发、动物养殖以及资源多样性保护提出了策略性建议。