Effects of controlled grazing on a degraded dwarf shrub,annual grass semidesert vegetation type of northwestern Kenya

A degraded dwarf shrub, annual grass semidesert vegetation type in Turkana, northwestern Kenya, was protected from livestock grazing from October 1985 to December 1990. The effects of controlled grazing on plant cover, litter cover and bare ground were monitored to appraise the trend in range condition using grazed transects (GT) and ungrazed transects (UGT). Despite an initial increase, plant cover on the UGT deteriorated in a similar manner to that on the GT. At the conclusion of six years of protection, the cumulative mortality of Indigofera cliffordiana on the UGT exceeded 60 per cent whereas on the GT it was 6 per cent. Furthermore the density of I. cliffordiana on the protected area decreased whereas that on the GT remained substantially unchanged. Aristida mutabilis replaced I. cliffordiana on the UGT but showed little change on the grazed area. Sedera hirsuta disappeared from the GT. On the UGT the percentage of bare ground, despite an initial decline (39.3 ± 7.3 per cent), increased substantially (68.9 ± 15.7 per cent) in parallel with the GT (77.3 ± 4.7 per cent). The results contradict a commonly held view that land degradation only occurs when plants are overused. The findings suggest that degradation can occur in the absence of grazing, especially if the plant species involved are dependent on perturbation. As over-resting eliminates I. cliffordiana, it seems judicious to allow a 2-3 year deferral period followed by moderate grazing if it is to be optimally managed.     

Land degradation and livestock production in Zimbabwe's communal areas

This paper considers evidence of land degradation and its impact on livestock production systems in the communal areas of southern Zimbabwe. Various measures of rangeland degradation, using both primary and secondary production indicators, are examined. An apparent contradiction emerges between the high observed levels of soil erosion and the lack of impact on livestock production, as measured by population density trends, cattle production parameters, cumulative stocking levels and extraction rates. Farmers' observations of land degradation processes support the quantitative data. A possible resolution of the contradiction lies in an assessment of the spatial and temporal dimensions of degradation patterns; this points to the fact that current erosion is concentrated in areas that are not key grazing resources for cattle. The analysis suggests an agenda for degradation research that concentrates on evaluating the time span over which economic impacts of soil erosion are felt and assessing the spatial pattern of soil loss, with a special focus on key grazing resource patches.     

关于完善我国新农村社会保障制度的思考

本文分析了我国现阶段农村社会保障制度的特点和存在的问题,对完善我国新农村社会保障制度提出了建议。     

三种处理的玉米秸型优化日粮肥育肉牛效果的研究

将15头草原红牛平均分成3组,1、2、3组依次饲喂青黄贮玉米秸型日粮、玉米秸饲料块型日粮和玉米酒糟型日粮,进行268d的饲养试验,然后屠宰。1、2、3组试验牛的日增重依次为1022g、1140g和1186g;屠宰率依次是57.44%、58.73%和58.31%;净肉率依次是48.35%、50.06%和49.45%。各种饲料和活牛价格按时价计算,经济效益最好的日粮是玉米酒糟型,其次是玉米秸饲料块型,青黄贮玉米秸型效益较差。     

发展小城镇的意义与策略

加速发展小城镇是21世纪我国实现农村现代化的战略抉择，创新土地制度，全面规划小城镇建设，加快调整乡镇行政区划，改革户籍制度，放宽融资政策，推进科教兴镇是行之有效的策略。     

快速环道建设过程中乡村地表水系

随着城市的发展、城区面积的扩大，为了解决城市繁重的交通任务、满足城市交通的快捷需求,快速环道建设成了满足城市交通要求的重要途径。快速环道建设过程中会给所经过的原有乡村地表水系造成破坏，科学、合理、及时地恢复、完善快速环道建设过程所破坏的乡村地表水系并使之和城市发展有机地结合，是城市快速环道建设中一项重要任务。     

ESTIMATION OF ABUNDANCE AND DISTRIBUTION OF MOOSE POPULATION IN CHINA

The geographical distribution and the abundance of Moose(Alces alces)popula-tion were studied in Northeastern China between 1985 and 1987,309 trails on the snow crossingthe 2,446km sampling lines were counted.The Moose range had been shrunked to northwest for100-200 km since 1976,and at present they covered an area about 190,000 km~2.The densitiesvaried from 0.0187 Mooses/km~2 to 0.1226 Mooses/km~2 and the average was 0.0519Mooses/km~2.The Moose population size was 9,955±397 Mooses(α=0.2,P=84.5%),about7000 of them was distributed in Daxinganling Mountains and the others were in XiaoxinganlingMountains.The present population had decreased to 53.4%in 1976,and the annual decreaserate was 6.27%.At present,Moose population is likely rare in China and should be strictly pro-tected.     

草甸草原草地基况与生物多样性关系的研究

对草甸草原不同放牧强度草地基况和生物多样性关系的研究表明：随着放牧强度的增大,草地基况水平表现出减低趋势,而且3个放牧强度区（轻度放牧区、中度放牧区、重度放牧区）的草地基况水平显著低于无放牧区（P〈0.05）,重度放牧区显著低于轻度和中度放牧区（P〈0.05）;随着放牧强度的增大,多样性指数（H′、D）、丰富度指数（Pa）和均匀度指数（JP、Ea）表现出先增加后减少的趋势,但在不同放牧强度区之间不存在显著差异（P〉0.05）;草地多样性指数与草地基况分值之间呈一种钟型曲线关系,即草地基况水平极劣或极好时,草地的生物多样性水平低,当草地基况水平良好时,草地的生物多样性水平较高。     

县域土地利用变化的生态环境效应评价——以三峡库区丰都县为例

以丰都县1997—2004年的土地利用现状为依据，在定性分析土地利用变化对生态环境造成的影响基础上，采用层次分析法构建土地利用变化生态环境影响评价体系，进而对丰都县土地利用变化对生态环境的影响进行评价。研究表明：近几年丰都县土地利用变化对生态环境的影响正效应显著，但是参照国家生态区的标准，丰都县的生态环境质量还处于相对较低的水平。     

论道德建设与以德治国

道德建设是以德治国的题中应有之义。道德是实现人生价值的保障 ,是调整人类行为的规范 ,是提高公民素质的根本 ,道德具有强大的社会功能。道德建设是建设有中国特色社会主义的经济、政治、文化的必然要求。要积极探索道德建设的有效途径 ,并建设与社会主义市场经济相适应的道德体系