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排序方式: 共有237条查询结果,搜索用时 15 毫秒
91.
Gregory M. Skupien Kimberly M. Andrews Lincoln R. Larson 《Human Dimensions of Wildlife》2016,21(3):264-279
Growing populations of American alligators (Alligator mississippiensis) in human-dominated landscapes present a challenge to wildlife managers concerned with promoting coexistence between humans and alligators. Where structural fixes such as direct removal of animals are not viable options, cognitive fixes such as conservation education programs should be considered. We evaluated the effectiveness of two conservation education programs (classroom-based program, field excursion) on three outcome variables that help define wildlife acceptance capacity for American alligators: beliefs and attitudes, perceived risk, and potential for coexistence. We found respondents who took part in both education programs had more positive beliefs and attitudes toward alligators, and believed in a greater potential for coexistence than individuals in a control group who did not undergo either intervention. Control group respondents also perceived higher risk from alligators. These data suggest that conservation education programs can impact stakeholder beliefs, attitudes, and perceptions, ultimately influencing acceptance capacity for predators. 相似文献
92.
93.
Qiufeng Zeng Xueqin Huang Yuheng Luo Xuemei Ding Shiping Bai Jianping Wang Yue Xuan Zhuowei Su Yonggang Liu Keying Zhang 《畜牧与生物技术杂志(英文版)》2015,6(1)
Background
Previous studies with broiler have shown dietary supplementation with multi-enzyme complex containing non-starch polysaccharides (NSP) degrading enzymes and phytase is efficient in releasing phosphorus (P), calcium (Ca), energy and amino acids from corn-soybean meal diets or corn-sorghum diets, hence compensating considerable levels of nutrients in formulation. Notwithstanding, such potentials have not been well defined in duck nutrition. Giving China being the largest duck producing country, we conducted this study to establish adequate specifications of major nutrients along with multi-enzyme complex to meat duck from day-old to slaughter, focusing on performance, utilization of nutrients and bone mineralization. Five dietary treatments were: Positive control (PC,T1 ): the nutrients concentration of diet for 1 to 14 d of age were apparent metabolizable energy(AME) 2,800 kcal/kg, crude protein (CP)19.39%, Ca 0.85%, available phosphorus (avP) 0.42%; for 15 to 35 d of age these parameters were AME 2,900 kcal/kg, CP 16.47%,Ca 0.76%,avP 0.38%; Negative control 1(NC1,T2), the AME and digestible amino acids (DAA) were reduced by 70 kcal/kg and 2.0%, avP and Ca by 1.0 g/kg from PC diet; Negative control 2( NC2,T4), the down-spec from PC diet was AME 100 kcal/kg, DAA 2.5%, avP 1.5 g/kg and Ca 1.2 g/kg; The enzyme complex was added at the same dosage (200 mL/ 1,000 kg) on NC1 (T3) and NC2 (T5) diets.Results
Comparing with the ducks fed on T1, T3 and T5 diets, the birds fed on NC2 diet showed the lowest (P < 0.05) body weight ( d 14 and 35), feed intake (d 35), tibia ash, Ca and P contents (d 14 and 35), and the utilization of nutrients (P < 0.05). The supplementation with the enzyme complex to the NC diets restored growth rate, utilization of nutrients and bone mineralization to the level of the PC diet, and increased AME by 60 kcal/kg and 117 kcal/kg, respectively for the NC1 and NC2 diets.Conclusion
These results suggest that down-spec AME by 100 kcal/kg, DAA by 2.5%, avP by 1.5 g/kg and Ca by 1.2 g/kg caused detrimental effects on duck performance compared with those fed on the PC diet, and these performance losses can be compensated by the addition of the multiple-enzyme complex. 相似文献94.
基于低空可见光谱的植被覆盖率计算 总被引:2,自引:0,他引:2
[目的]将低空遥感技术应用到水土保持设施验收中,从可见光谱遥感影像提取区域植被信息,提出可准确、客观计算水土保持设施验收指标中植被覆盖率的方法,以减少工作人员的业外工作量,提高测算效率。[方法]将仅含有可见波谱信息的低空遥感图像作为研究对象,在利用植被指数红绿比指数(RGRI),过绿指数(EXG),可见光波段差异植被指数(VDVI),归一化绿蓝差异指数(NGBDI)和归一化绿红差异指数(NRGRDI)分析图像波谱特性的基础上,采用双峰直方图法和最大熵值法确定各植被指数的阈值,再使用ENVI软件提取图像的植被信息,并计算植被覆盖率,与参照结果进行比对。[结果]利用可见光谱差异指数(VDVI)提取的植被信息精度高达95.32%。由此计算得到的植被覆盖率为54.43%,与实际情况最为接近。[结论]基于可见光谱遥感影像计算植被覆盖率的方法具有可行性,该方法人工干预少,结果准确度高,可为水土保持设施验收提供实时的数据支撑。 相似文献
95.
氮肥利用率是一个评价施氮产量效益和环境效应的重要指标,这个指标的计算和测定存在计算结果偏低和结果变异大的问题,希望通过研究提出规范、科学、合理的氮肥利用率测定方法。采用长期氮肥检测定位试验结果,分析空白对照和施肥处理小麦产量的逐年变化特征,应用常规差减法计算氮肥利用率,研究其年际间变化特点,提出测定氮肥利用率的规范的探讨。氮肥利用率测定规范:第一,空白对照吸收氮素达到相对稳定;第二,施肥处理作物吸收氮素量相对稳定;第三,必须采用稳定期内若干年的平均值。通过规范化的测定和计算,能够计算出比较合理的氮肥利用率参数,在施肥量120~180 kg N·hm-2范围内的氮肥利用率为69.2%~76.2%。建议氮肥利用率的测定遵循一定的测定规范,通过制定测定规范,测定出正确合理的氮肥利用率参数具有可比性,便于应用于科研和生产。 相似文献
96.
97.
Chrysanthi Charatsari Alex Koutsouris Evagelos D. Lioutas Apostolos Kalivas Eleni Tsaliki 《Journal Of Agricultural & Food Information》2018,19(1):66-74
Farmer field schools (FFS) represent an alternative lifelong learning approach aimed at enhancing farmers' competences and skills through nonformal education. In this study we examined if farmers' participation in FFS is motivated by their social-psychological needs and whether these needs can be fulfilled through participation in FFS. Findings revealed that the possibility to participate in FFS is higher for farmers who experience lower levels of closeness and connectedness with their community peers and for those who score low on belongingness satisfaction. Furthermore, our analysis confirmed that FFS attendance increases felt community acceptance and facilitates the satisfaction of the belongingness need. 相似文献
98.
邱永忠 《福建农业大学学报(哲学社会科学版)》2011,(3):95-98
由于仿拟修辞符合语言表达的经济性原则,因此在英汉语言中成为常见的修辞现象。要有效地将仿拟修辞表达在译文中呈现,传递给他民族的读者群体,就不得不观照表达与接受主体的社会性因素,包括受英语表音性和汉语表意性特点的影响而在仿拟过程中体现的不同语言使用偏好。仿拟翻译应顺应英汉民族社会性的语言使用偏好,采取优先保留仿拟修辞的策略,以实现源语文本跨语符的修辞交际功能。 相似文献
99.
根据退耕还林工程阶段验收工作的具体业务需求,从具体应用实际出发,采用.NET框架的C#开发语言与GIS二次开发组件,编制一套具有逐级管理模式的地理信息系统,其采用省、县、乡三级管理模式,实现对退耕地块空间数据的GPS信息成图、图形面积核算、图形编辑,属性数据的增加、删除、修改、汇总、统计、打印信息表等功能,最终实现验收资料图、表、卡统一管理。此系统的建立对实现软件化、规范化、流程化管理起到了积极性和关键性的作用。 相似文献
100.
With the development of Web application,virtual reality technology based on Web is popular.In Web3D field,the old standard of VRML(Virtual Reality Modeling Language)has many problems and is not fit for the development.So the Web3D Consortium provides a next generation standard for Web3DX3D(Extensible 3D specification).X3D,using multiple file encodings describing the same abstract model including XML,has a modular architecture allowing a range of levels of adoption and support for many different market types.It also has a unified application programming model and an expanded specification structure.The technology character of X3D is mainly analyzed.Also the background,development and supporting tools of X3D are introduced.And then an example of application using X3D is given. 相似文献