Determination of growth-stage-specific crop coefficients (KC) of maize and sorghum

A ratio of crop evapotranspiration (ET_C) to reference evapotranspiration (ET_O) determines a crop coefficient (K_C) value, which is related to specific crop phenological development to improve transferability of the K_C values. Development of K_C can assist in predicting crop irrigation needs using meteorological data from weather stations. The objective of the research was conducted to determine growth-stage-specific K_C and crop water use for maize (Zea Mays) and sorghum (Sorghum bicolor) at Texas AgriLife Research field in Uvalde, TX, USA from 2002 to 2008. Seven lysimeters, weighing about 14 Mg, consisted of undisturbed 1.5 m × 2.0 m × 2.2 m deep soil monoliths. Six lysimeters were located in the center of a 1-ha field beneath a linear-move sprinkler system equipped with low energy precision application (LEPA). A seventh lysimeter was established to measure reference grass ET_O. Crop water requirements, K_C determination, and comparison to existing FAO K_C values were determined over a 3-year period for both maize and sorghum. Accumulated seasonal crop water use ranged between 441 and 641 mm for maize and between 491 and 533 mm for sorghum. The K_C values determined during the growing seasons varied from 0.2 to 1.2 for maize and 0.2 to 1.0 for sorghum. Some of the values corresponded and some did not correspond to those from FAO-56 and from the Texas High Plains and elsewhere in other states. We assume that the development of regionally based and growth-stage-specific K_C helps in irrigation management and provides precise water applications for this region.     

Predivinsk Lespromkhoz: A Case Study on the Collaborative Restructuring of a Forest Product Based Community in Siberia

Abstract

Ecologists, managers, federal forest officials, biologists, Russian and international environmentalists are developing and rethinking the practices and products of a timber operation in central Siberia. Predivinsk Lespromkhoz is a timber producing community located on the Einisei River, 150 kilometers north of Krasnoyarsk in central Siberia. The four thousand inhabitants are faced with expanding costs, a loss of financial support from the government, a collapsed market and disappearing natural resources. The restructuring of the Russian Government gave local foresters and limber operations more control of their resources but unfortunately, inflation and the dwindling economy restricted capital for implementation of new, sustainable forest practices and improved marketable products. Predivinsk is relatively accessible to foreigners interested in the taiga of central Siberia and scientists from the Krasnoyarsk Forest Institute welcome collaborative projects.     

刑法中严格责任的归责原则及适用

严格责任作为刑法中的一种归责原则,是英美法系国家刑法理论的一个特色。严格责任的存在有其合理性,值得借鉴,以构建符合我国国情的严格责任理论。     

开放式公园景观设计——以杭州市钱江新城市民公园为例

从开放式公园的性质出发，探讨了开放式公园的地位、作用与景观设计原则，并以杭州市钱江新城市民公园为例，对开放式公园的景观设计要素进行了分析，并总结了杭州市钱江新城市民公园的景观设计方法。     

牛鲜粪便转化民用燃料原料配方的筛选

养牛业已成为我国农业经济发展和畜牧业生产中的一个重要支柱产业,规模集约化发展的同时所产生大量粪便等污物得不到有效环保处理,对环境造成了严重污染。本文采用正交试验,将奶牛鲜粪便、煤粉、除臭吸附粘合剂原料均匀混合处理,对牛鲜粪便转化民用燃料技术环保再利用进行了研究,结果表明,含水量较高的奶牛鲜粪便最低利用率可达40%,除臭吸附粘合剂最适合添加比例为11%,就可及时将牛鲜粪便中大量粪水和挥发性污染大气有害气体吸附固定住,也便于加工成多种形状的民用燃料加以再利用,具有强大的环保功能和鲜粪便循环再利用特点,对推动养牛业健康可持续发展具有重大意义。     

“三权分置”下落实宅基地集体所有权的政策逻辑、困境与路径——以民法典为视角

落实宅基地集体所有权是筑牢农村集体经济基本盘的客观需要,契合了农村产权制度改革必须坚守集体所有底线的基本逻辑。本文基于《民法典》视角,阐释落实宅基地集体所有权的政策逻辑,分析其在实践过程中面临的现实困境,探讨“三权分置”下落实宅基地集体所有权的实践路径。研究表明,落实宅基地集体所有权对于巩固集体经济组织主体地位、保障农民财产权利和实现农村共同富裕具有重大的实践价值。然而,受困于农民集体所有权行使主体虚化、宅基地利益主体复杂多元和宅基地使用权主体“封闭性”等多重因素,落实宅基地集体所有权也面临着诸多困难与挑战。学术界需要加强法治实践研究,需要将宅基地集体所有权研究放置于国家法治建设的逻辑之下,在学术研究与法治建设之间形成一种良性的互动关系。因此,建议结合《民法典》的相关规定,围绕着处理好农民与土地关系这条主线,从明晰宅基地集体所有权主体、强化集体所有权权能、建立新型宅基地管理模式等方面探索农村宅基地集体所有权的实现路径。     

Ammonia Emissions from Broiler Houses

Air emissions will be one of the greatest challenges facing the poultry industry in the future. Federal regulations as applied to animal agriculture will be further defined as additional baseline data are obtained. Ammonia emissions monitoring requires accurate ventilation estimates, ammonia detection, and trained personnel. There are wide variations in ammonia emissions among houses, ages of birds, and flocks. Ammonia emission levels per house occasionally exceed the threshold of 45 kg /d (100 lb/d) set by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and Emergency Planning and Community Right to Know Act (EPCRA). In the future poultry producers may need to address ammonia emissions when adopting best management practices for their operations.     

《土木工程材料》课程教学改革研究的探索

针对《土木工程材料》教学中存在的问题,探索《土木工程材料》的教学内容、教学方法、教学手段和教学实践环节等方面的改革,应重视实践教学,提高学生理论联系实际及综合运用理论知识的能力。