2019电大《试验设计与生物统计》作业一答案（第一到二章）

电大《试验 设计 领导形象设计圆作业设计ao工艺污水处理厂设计附属工程施工组织设计清扫机器人结构设计 与生物统计》作业一（第一到二章） 1、什么是田间试验？田间试验的主要特点是什么？ 在田间土壤、自然气候等环境条件下栽培作物，并进行与作物有关的各种科学研究的试验。 田间试验有两个特点：（1）研究对象和材料是生物体本身，由农作物和其它生物体本身的反应来直接检测试验的效果，试验材料本身便存在产生试验误差的多种因素；（2）是在开放的自然条件下进行的，因而田间试验的环境条件存在导致试验产生误差。 2、对田间试验的要求有哪些？ （1）试验目的要明确 在大量阅读文献与社会调查的基础上，明确选 题 快递公司问题件快递公司问题件货款处理关于圆的周长面积重点题型关于解方程组的题及答案关于南海问题 ，制订合理的试验 方案 气瓶 现场处置方案 .pdf气瓶 现场处置方案 .doc见习基地管理方案.doc关于群访事件的化解方案建筑工地扬尘治理专项方案下载 。对试验的预期结果及其在农业生产和科学实验中的作用要做到心中有数。（2） 试验条件要有代表性：试验条件应能代表将来准备推广试验结果的地区的自然条件(如试验地土壤种类、地势、土壤肥力、气象条件等)与农业条件(如轮作 制度 关于办公室下班关闭电源制度矿山事故隐患举报和奖励制度制度下载人事管理制度doc盘点制度下载 、农业结构、施肥水平等)。（3）试验结果要可靠：在田间试验中准确度是指试验中某一性状(小区产量或其它性状)的观察值与其理论真值的接近程度；越是接近，则试验越准确。精确度是指试验中同一性状的重复观察值彼此接近的程度，即试验误差的大小，它是可以计算的。试验误差越小，则处理间的比较越为精确。（4）试验结果要能够重演：所谓重演性是指在相同条件下，再次进行试验或实验，应能获得与原试验相同的结果。 3、简述田间试验误差的来源 田间试验的误差来源： 1）试验材料固有的差异：包菜苗子大小、壮弱。 2）试验时农事操作和管理技术的不一致性所引起的差异：追肥不匀、浇水不均。 3）进行试验的外界条件的差异：如土壤肥力不均 4、控制土壤差异的小区技术有哪些方面？ （1）试验小区的面积 试验小区面积的大小，一般变动范围为6—60m2。而示范性试验的小区面积通常不小于330 m2。 （2）小区的形状 :在通常情形下，长方形尤其是狭长形小区，容易调匀土壤差异，使小区肥力接近于试验地的平均肥力水平。亦便于观察记载及其农事操作。 （3）重复次数 重复次数即每一处理的试验小区数，试验设置重复次数越多，试验误差越小。小区面积较小的试验，通常可用3—6次重复；小区面积较大的，一般可重复3—4次。进行面积大的对比试验时，2次重复即可。 （4）对照区的设置 田间试验应设置对照区(以CK表示)，作为处理比较的标准。对照应该是当地推广良种或最广泛应用的栽培技术措施。 （5）保护行的设置 保护行种植的品种，可用对照种，最好用比供试品种略为早熟的品种，以便在成熟时提前收割，既可避免与试验小区发生混杂。 　5、实施田间试验的原则是什么？ 实施田间试验的原则是：1.重复 试验中同一处理种植的小区数即为重复次数。重复的作用是估计试验误差。试验误差是客观存在的，但只能由同一处理的几个重复小区间的差异估得。重复的另一主要作用是降低试验误差，以提高试验的精确度。2.随机排列 随机排列是指一个区组中每一处理都有同等的机会设置在任何一个试验小区上，避免任何主观成见。3.局部控制 局部控制就是将整个试验环境分成若干个相对最为一致的小环境，再在小环境内设置成套处理，即在田间分范围分地段地控制土壤差异等非处理因素，使之对各试验处理小区的影响达到最大程度的一致。 6、田间抽样有哪几种 方法 快递客服问题件处理详细方法山木方法pdf计算方法pdf华与华方法下载八字理论方法下载 ？ 按抽选观察单位方法的不同为三大类 （1）随机抽样（概率抽样）：在抽选单位时，总体内所有各单位均有同等机会被抽取即具有相等的被抽取概率。 （2）顺序抽样（机械抽样，等距抽样）：将总体全部抽样单位按自然顺序编号，分为相等单位数量的组，组数等于拟从总体抽出的单位数目，然后随机地从第一组内抽取一个单位，间隔相等编号距离在第二组抽取另一单位，直至抽出所需全部单位。 （3）典型抽样：按研究目的从总体内有意识地、有目的地选取有代表性的典型单位或单位群，至少要求所选单位能代表总体的绝大多数，该法称典型抽样，用该法选取的样本称典型样本。多依赖调查者的经验，无法估计抽样误差。 Visa-free policy brings Chengdu biz, tourism boost. Making national headlines several times, Chengdu's 72-hour visa-free policy has attracted wide attention from both Chinese and foreign experts and businessmen since it took effect on Sept 1 last year. The program permits citizens from 51 countries and regions including the United States, Australia, Canada and Japan who have valid visas and flight tickets to a third country to spend three days in the city. The capital of Sichuan province is the first city in the western region of China to offer foreign tourists a three-day visa and the fourth nationwide to adopt the policy following Shanghai, Beijing and Guangzhou. Li Zhiyong, deputy dean of the tourism institute at Sichuan University, said the move "contributes to a large increase in the number of overseas tourists and raises the city's level of internationalization". "The policy will also bring direct economic revenue," Li said. "Chengdu has many cultural legacies and is also a paradise for panda lovers with the world's largest breeding and research center. Three days are long enough for foreign visitors to visit those iconic tourist spots," he noted. The city is home to the remains of the Jin sha civilization that dates back more than 3,000 years as well as the Qing cheng Mountains and the Du jiang yan irrigation system. Qing cheng has long been recognized as the birthplace of Taoism, China's ancient indigenous religion, while Du jiang yan is considered to be the oldest functioning water-control project in the world. Chengdu ranked third in tourist facilities, management and services among 60 Chinese cities in a customer satisfaction survey released last year. But, Li added that efforts are still needed to develop more tourism products, improve English services and provide accurate translation of traffic signs and scenic billboards. Zhao Yun, chairwoman of British Chamber of Commerce Southwest China, told China Daily that his colleagues found the policy very convenient. "A British client once flew here and stayed for just one day to check her ordered goods," she said. Zhao was born in Shanxi province, but she has lived in Chengdu for more than 10 years. "My life was like a running race moving from place to place. I also lived in Beijing and Shanghai before," she said. "But Chengdu is a place that you never want to leave once settling down. It is now my second hometown," she said. If the environment is further improved, the city will attract more people to visit and live, with the 72-hour visa-free policy and compelling conditions in transportation, culture, climate and cuisine, he said. Foreigners also gave positive feedback on the policy. A spokesman from Dell Inc said the company has a global hub of operation in Chengdu, so the three-day visa "has an immediate and positive influence on the company's business development". Rudy Buttignol, president of the public broadcasting company in British Columbia, Canada, said his work requires frequent travel to Chengdu and the policy "makes the trips easier". Data from the city's public security bureau shows some 100 foreign visitors enjoyed the 72-hour policy by the end of March, most of them from the United States, the United Kingdom and Germany. Chengdu also reported robust growth in its overall tourist industry last year. Official statistics show that it received some 150 million tourists last year, an increase of 28 percent from 2012. Around 1.7 million came from abroad, an increase of 12 percent. Total revenue from tourism surpassed 133 billion yuan ($21.7billion). During his visit to Kazakhstan in September, Chinese President Xi Jinping proposed that China and Central Asia join hands to build a Silk Road economic belt to boost cooperation. The idea has been widely echoed in Central Asian countries, becoming an encouraging blueprint for Chinese areas along the Silk Road that has linked Asia and Europe for more than 2,000 years. In the next three weeks, China Daily reporters will travel through the belt in China and in Kazakhstan, Uzbekistan and Turkey. They will show the progress and expectations of the countries, businesses and peoples on the route. Shaanxi - the start of the ancient Silk Road - has positioned itself as the new starting point for the development of the Silk Road Economic Belt, which will strengthen China's cooperation with Central Asian countries, a senior official said. Shaanxi Governor Lou Qinjian said the province is fresh, rich and unique, as it was when it anchored one end of the ancient Silk Road. "It is the best option for accommodating industrial transfers from East China or the world at large," he said on Wednesday in Xi'an. Lou held a joint interview with 27 media, including China Daily, the first in a series of interviews entitled Chinese Media Along the Silk Road. The interviews will be in Shaanxi and Gansu provinces and the Xinjiang Uygur autonomous region, as well as Kazakhstan, Uzbekistan and Turkey. The media group held the first interview on Wednesday morning in Xi'an, the starting point of the ancient Silk Road, a trade channel established more than 2,000 years ago linking China, Central Asia and Europe. 整理范文，仅供参考 欢迎您下载我们的文档 资料可以编辑修改使用 致力于合同简历、论文写作、PPT设计、计划书、策划案、学习课件、各类模板等方方面面，打造全网一站式需求 觉得好可以点个赞哦 如果没有找到合适的文档资料，可以留言告知我们哦