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1.
不同种植方式对甜菜产质量的影响   总被引:2,自引:2,他引:0  
试验结果表明,在同等条件下,由于栽培方式不同,密度不同,块根产量、产糖量差异较大,以纸筒大垄双行为最好,甜菜块根产量、产糖量比对照小垄直播分别提高36.7%、39.8%,每公顷纯增效益1602元。其次是大垄双行覆膜,块根产量、产糖量比对照小垄直播分别提高31.5%、33.1%。  相似文献   
2.
根据不同区域气候特点和产量水平,运用系统工程理论中的线性规划方法对该市的作物种植结构进行了调整,在种植面积基本不变的情况下,净产值增加了15.3%和17.3%;并在不同的气候区域设计了不同作物种植的最佳组合方案。这对增加农业种植效益和农民收入,有效改善生态环境,保持农业的可持续发展等方面都具有显著的经济、社会和生态效益。  相似文献   
3.
乌梁素海湿地环境与资源地理信息系统的研究   总被引:6,自引:0,他引:6  
本系统建立乌梁素海湿地基础地形库、生态库、资源库、工程档案库、遥感影像库等基础数据库及信息发布系统 ,使 GPS、GIS、RS紧密结合 ,同时实现了专家决策支持系统与地理信息系统之间的一体化集成。本系统可以为乌梁素海湿地生态治理与资源开发提供全方位的数据信息及其管理 ,对生态工程规划与实施方案进行优化设计 ,并提供实时监控服务。  相似文献   
4.
Increasing urbanization of rural landscapes has created new challenges for wildlife management. In addition to changes in the physical landscape, urbanization has also produced changes in the socio-cultural landscape. The greater distancing from direct interaction with wildlife in urbanized societies has led to the emergence of a culture whose meanings for wildlife are less grounded in the utilitarian/instrumental orientation of rural agrarian systems. Urban perspectives on wildlife are comprised of more highly individualized emotional/symbolic values. This shift creates two problems with respect to managing wildlife in an urbanizing landscape. First the increased diversity in values and meanings increases the likelihood for social conflicts regarding wildlife management while at the same time making socially acceptable resolutions more intractable. This in turn requires fundamental changes in decision-making paradigms and the research approaches used to inform decision making. Second, as remaining rural communities feel the pressures of urbanization, wildlife conflicts become conflicts not just over wildlife but conflict over larger socio-political concepts such as equity, tradition, private property rights, government control, power, and acceptable forms of knowledge. This paper examines the wildlife management implications of changes associated with increasing urbanization and employs two case studies to illustrate these issues. First a study of a controversy over urban deer management provides insights into how to map conflicting values and search for common ground in an urban culture with increasingly individualistic values for wildlife. Specifically, the analysis illustrates that common ground may, at times, be found even among people with conflicting value systems. The second case study examined a ranching community faced with predator reintroduction. This case study illustrates tensions that occur when the community of interest (i.e. a national public) is broader than the community of place in which the problem occurs. In this latter situation, the debate centers around more than just different views about the rights of animals. It also entailed the rights of individuals and communities to decide their future. The conclusion discusses the need for wildlife institutions to adapt their underlying decision making philosophy including the way science is integrated into decision making processes in light of the changes in social context caused by urbanization.  相似文献   
5.
种植方式与种植密度对大力士高粱的影响   总被引:1,自引:0,他引:1  
本试验用裂区设计,研究了大力士高粱在16种不同种植密度、3种种植方式下,产草量、生产速度、茎叶比、茎粗的变化情况。结果表明,在撒播密度为18 kg/hm2、条播为22.5 kg/hm2、穴播为28.5 kg/hm2时达到最高产量;生长速度在第53-55 d时最高,达5.7 cm/d;茎叶比随着产量的增加逐渐减少;茎粗随着种植密度的增大而有减小的趋势。  相似文献   
6.
Decision support systems (DSSs) are indispensable tools in preparing a forest management plan for a better combination of multiple forest values. This study attempted to develop and explain a stand-based forest management DSS (Ecosystem-based multiple-use forest planning [ETÇAP]) comprising a traditional simulation, linear programming (LP), metaheuristics and geographic information system. The model consists of five submodels; traditional management approach to handle inventory data, an empirical growth and yield model, a simulation to conceptualize management actions, a LP technique to optimize resource allocation and a simulated annealing approach to directly create a spatially feasible harvest schedule. The ETÇAP model has been implemented in a comparative two case study areas; Denizli–Honaz and Akseki–Ibrad?. Both simulation and optimization models outperformed to the traditional management plan. The periodical change of growing stock, allowable cuts, carbon sequestration and water production are used as performance indicators. The results showed that more amount of wood could be harvested over time compared to traditional level of harvesting. It could be concluded that various management strategies allowed managers to stimulate more decision options for better outputs through intertemporal trade-offs of management interventions as the model provided tools to quantify forest dynamics over time and space. Challenges exist to establish the functional relationships between forest structure and values for better quantification and integration into the management plans.  相似文献   
7.
太行红石榴喜光、耐旱、怕涝、怕寒冷,适宜在pH值在4.5~8.2之间的砾质或沙质壤土中栽植。文章介绍了石榴树的栽培养护技术,包括扦插育苗、移栽定植、幼树期管理、结果期管理等。  相似文献   
8.
Dense planting and less basal nitrogen (N) fertilization have been recommended to further increase rice (Oryza sativa L.) grain yield and N use efficiency (NUE), respectively. The objective of this study was to evaluate the integrative impacts of dense planting with reduced basal N application (DR) on rice yield, NUE and greenhouse gas (GHG) emissions. Field experiments with one conventional sparse planting (CK) and four treatments of dense planting (increased seedlings per hill) with less basal N application were conducted in northeast China from 2012 to 2013. In addition, a two-factor experiment was conducted to isolate the effect of planting density and basal N rate on CH4 emission in 2013. Our results show that an increase in planting density by about 50% with a correspondingly reduction in basal N rate by about 30% (DR1 and DR2) enhanced NUE by 14.3–50.6% and rice grain yield by 0.5–7.4% over CK. Meanwhile, DR1 and DR2 reduced GWP by 6.4–12.6% and yield-scaled GWP by 7.0–17.0% over CK. According to the two-factor experiment, soil CH4 production and oxidation and CH4 emission were not affected by planting density. However, reduced basal N rate decreased CH4 emission due to it significantly reduced soil CH4 production with a smaller reduction in soil CH4 oxidation. The above results indicate that moderate dense planting with less basal N application might be an environment friendly mode for rice cropping for high yield and NUE with less GHG emissions.  相似文献   
9.
为了筛选适宜曲周县后老营村农业生产的较优种植体系并设计更好的种植体系,采用随机抽样调查的方法,对该村主要作物的种植体系及其水肥资源利用状况和经济效益进行了详细调查。结果表明:棉花-西瓜套作体系的水肥资源利用率最高,小麦-西瓜-玉米间套作体系的经济效益最好,棉花-西瓜套作体系次之,二者差异不显著。未来可以基于这2种种植体系重新设计新的种植体系,从而在生态、经济、环境等方面取得较好的综合效益。  相似文献   
10.
[目的]研究"早稻-冬草莓"轮作模式最佳种植期.[方法]根据双流县气象局1971 ~ 2010年气象资料,采用滑移气候相似距及数理统计方法,对"早稻-冬草莓"轮作模式最佳种植期进行分析.[结果]冬草莓最佳种植期在8月1日~翌年3月31日,其小苗移栽最早在7月中旬,最晚在8月中旬,最佳移栽时期平均在8月19日.早稻移栽时间平均为3月26日,拟收获期平均为7月26日.[结论]从气象角度研究了"早稻-冬草莓"轮作模式最佳种植期,为双流县推广该模式,最大限度地发挥光、温、水、土地的生态效益提供了科学的决策依据.  相似文献   
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