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121.
林业信息化建设与林业生态文明的战略关系研究 总被引:1,自引:0,他引:1
林业信息化是实现林业现代化建设的基础和重要标志。信息化可以为林业经济发展节约资金,实现资源共享,带来显著的社会、生态和经济效益。生态文明作为现代林业建设的战略目标,必须采用当前各种新颖技术来促进和实现。信息化是各行各业正在实施的目标,在建立生态文明的历程中如何利用信息技术的优势,如何用信息化手段来评价和促进林业生态工程是我们要思考的课题。本文着力探讨林业信息化在建设现代生态林业过程中的若干重要问题,紧扣生态文明这一当前流行主题,研究信息化技术在现代生态林业建设过程中的作用、手段、评价标准和互动关系等。 相似文献
122.
LIZhao-hua MikioKOBAYASHI 《林业研究》2004,15(3):233-242
In the past, utilization of bamboo resources in China has been traditionally dominated by direct consumption of local farmers as minor forest products with weak linkage with market. In recent years, the over-supply of grains and rapid degradation of agricultural environment call for alternative crops that can be developed through integrating the environmental plantation with the market demands. Closely associated with forestry and agriculture, bamboo is able to deal with the new challenges which China‘s agriculture is facing. Of 534 documented bamboo species in China, 153 species produce edibleshoots and of which 56 species are recommended for agricultural plantation; 139 species provide timbers and of which 58 species recommended; 116 species can be splited as good strips for weaving and of which 22 species recommended; 88 species are considered as garden bamboos and of which 34 species recommended; 45 species are able to produce paper pulp and of which 18 species recommended. 相似文献
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124.
Animal pollination is one of the essential services provided by ecosystems to humans. In the face of a potential worldwide pollination crisis it is important to assess which countries may be more vulnerable in order to prioritize pollinator conservation efforts. The poverty level, the population density and the level of pollinator dependence for food provisioning are key aspects to identify vulnerable countries. We evaluate these aspects and determine the level of human food provisioning dependence on pollinators in Mexico, a developing and highly populated country. The diversity of crop species in Mexico is exceptionally high. Nearly 85% of fruit and/or seed consumed species depend to some degree on pollinators for productivity. Overall, pollinator-dependent crops generate larger income but cover a lower cultivated area and produce less volume compared to non-pollinator-dependent crops. Volume per unit area, however, as well as revenue per unit area, is much higher for pollinator-dependent crops. Native wild pollinators also play a key role in fruit or seed production of Mexican domesticated plant species and in the reproduction of many useful wild species. Thus, assuring free pollination services is particularly important in Mexico as the livelihood of a large proportion of the population exclusively and directly depends on ecosystem services for subsistence. Feasible conservation strategies involve the payment of environmental services to Ejidos (communal land tenure systems) making efforts to protect or restore plant resources and native pollinators, and the creation of new protected natural areas, which ensures food provision, mating and nesting sites for pollinators. 相似文献
125.
以江西水土保持生态科技园为研究区,通过无人机遥测技术以及地理信息系统,对生态果园水土保持措施进行图斑化、信息化管理研究.结果表明:无人机遥测技术获取的不同阶段的航飞影像可用于生态果园改造的动态监测;利用Agisoft photoscan软件处理航飞影像可生成高分辨的数字正射影像(DOM)以及数字地表模型(DSM)数据;利用生成的DOM,结合地理信息系统,可获取生态果园水土保持措施的分布、数量、长度等信息,建立生态果园水土保持措施数据库,并输出报表和专题图.经与实际量测长度验证,基于DOM提取的长度平均精度为97.99%;与实测坡度验证,基于DSM数据提取的坡度平均精度为88.91%.无人机遥测技术能够快速、准确、自动获取地物的面积、长度、坡度等指标数据,可满足当前水土保信息化的要求,提升综合治理项目实施监测的信息化水平,提高施工监测的质量和效率. 相似文献
126.
《国际水土保持研究(英文)》2022,10(3):470-486
This study was performed to examine the separate and simultaneous influence of predictive models’ choice alongside sample ratios selection in soil organic matter (SOM). The research was carried out in northern Morocco, characterized by relatively cold weather and diverse geological conditions. The dataset herein used accounted for 1591 soil samples, which were randomly split into the following ratios: 10% (~150 sample ratio), 20% (~250 sample ratio), 35% (~450 sample ratio), 50% (~600 sample ratio) and 95% (~1200 sample ratio). Models herein involved were ordinary kriging (OK), regression kriging (RK), multiple linear regression (MLR), random forest (RF), quantile regression forest (QRF), Gaussian process regression (GPR) and an ensemble model. The findings in the study showed that the accuracy of SOM prediction is sensitive to both predictive models and sample ratios. OK combined with 95% sample ratio performed equally to RF in conjunction with all the sample ratios, as the latter did not show much sensitivity to sample ratios. ANOVA results revealed that RF with a ~10% sample ratio could also be optimum for predicting SOM in the study area. In conclusion, the findings herein reported could be instrumental for producing cost-effective detailed and accurate spatial estimation of SOM in other sites. Furthermore, they could serve as a baseline study for future research in the region or elsewhere. Therefore, we recommend conducting series of simulation of all possible combinations between various predictive models and sample ratios as a preliminary step in soil organic matter prediction. 相似文献
127.
农田长期生态过程的长期试验研究进展与展望 总被引:7,自引:0,他引:7
长期试验是研究农田长期生态过程及其环境效应和调控措施的重要手段.本文综述了国际上重要农业长期试验的研究发展趋势,分析了农业长期试验的重要作用,然后分析了国内农业长期试验网的发展现状,提出了未来发展的建议.农业长期试验的发展主要表现在长期农业生态和环境过程的研究领域不断扩展、长期试验成为多学科交叉研究平台和应用研究平台.国内建立了两个主要的农业长期试验网络,重点开展了水分和养分的长期试验.目前农业长期试验网络需要在区域尺度上加强农业、环境和生物科学的交叉研究;扩展试验地面积,完善试验设计;完善分析测试方法和样品、数据的保存系统.国家需要制定和实施稳定农业长期试验研究的管理和经费支持政策. 相似文献
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129.
本研究以河北省尚义县为例对坝上地区农业发展的可持续程度进行分析,发现尚义县的农业发展仍处于一种较为严重的不可持续状态,2000年尚义县农业人均生态赤字为0.36hm2,从近6年的状况看,其农业发展已经开始出现好转趋向。 相似文献
130.
We compared the composition and structure of primary forest avifauna among primary forests, selectively logged forests and mixed-rural areas (e.g. villages and agricultural areas) of Peninsular Malaysia. We found that forests that were selectively logged at least 30 years ago contained only 73-75% of the 159 species of extant primary forest birds, with an increased proportion of dominant species. We estimated that only 28-32% of the primary forest species utilized the mixed-rural habitat, and that the number of species that bred in the agricultural landscapes might be even lower. The microhabitat of different species most affected their vulnerability to disturbance. Most small, arboreal frugivores and omnivores, and insectivores that fed from tree trunks, showed greater persistence in the mixed-rural habitat than ground dwelling bird species, which were affected most by disturbance. Resource abundance and variables that were closely related to forest disturbance such as the density of large trees, density of dead trees, canopy cover density and shrub volume influenced the distribution of the primary forest birds. Large primary forest reserves and a revision of short-cycle logging regimes (ca. 30 years) are needed if we are to conserve the lowland rainforest avifauna of Peninsular Malaysia and other parts of Southeast Asia. 相似文献