Worker health and safety in concentrated animal feeding operations

A trend in consolidating livestock and poultry operations into concentrated animal feeding operations (CAFOs) potentially increases farm worker exposure to the hazards associated with high animal density conditions. The two main contributors of documented injury (fatal and non-fatal) are related to accidents with machinery and animals. Tractor rollovers are the leading accident in the area of farming machinery issues; kicks, bites, and workers being pinned between animals and fixed objects are non-machinery issues typically caused by inadequate precautions taken in the vicinity of livestock. These types of accidents are well documented; however, recommended safety strategies continue to be studied to reduce the risks and numbers of injuries associated with both machines and animals. Unlike accidents involving machinery and animals, air emission exposure and potential health effects from CAFOs are not well documented. CAFOs have the potential to show higher gaseous and particulate matter emissions compared to smaller farms. Pollutants like hydrogen sulfide, ammonia, volatile organic compounds, particulate matter, and endotoxin are emitted on CAFOs and can potentially affect worker health. These specific air emissions, their sources, and some of their harmful capabilities have been identified, and regulations have been implemented to create improved work environments on CAFOs. Despite such precautions, farm workers continue to report respiratory health symptoms related to their work environment. Air pollutant exposure and its health effects on farm workers require focused research to arrive at improved safety strategies that include mitigation techniques and protective gear to minimize adverse effects of working in CAFOs.     

Efficacy of leaf litter mulch to mitigate runoff and sediment yield following mechanized operations in the Hyrcanian mixed forests

Journal of Soils and Sediments - Following ground-based skidding operations, understory vegetation and litter layer are commonly damaged or displaced by the movement of machines and timber on the...     

Physical protection of soil organic matter following mechanized forest operations in Pinus radiata D.Don plantations

Mechanized forest operations have a large impact on soil systems, and may cause disruption of aggregates and exposure of previously protected soil organic matter to microbial attack. In this study, we investigated how C storage, soil structure and unprotected, physically protected and resistant C pools recover 0, 7 and 20 years after mechanical harvesting and site preparation in second rotation Pinus radiata D.Don plantations. We detected differences in dry mean weight diameter (DMWD) of aggregates, with higher DMWD in 0- and 7-year-old pine stands (8.7 and 7.5 mm, respectively) than in 20-year-old stands (4.1 mm). This was attributed to the compaction induced by heavy machinery, as reflected by the positive relationship between DMWD and bulk density (r = 0.85, P < 0.05). Organic C contents in the top 5 cm were similar 0 and 7 years after disturbance, but were twice as high after 20 years, with mean values of 25, 28 and 52 Mg C ha⁻¹, respectively. In addition, the resistant C pool was also reduced by up to 7% after clearance. In contrast, unprotected C and physically-protected C were greatest in the youngest stands, indicating that stand establishment and harvesting with heavy machinery may have broken soil aggregates and exposed the previously protected SOM to microbial decomposition and that forest operations may create new mega-aggregates able to protect organic residues. However, the lowest physically-protected C values in 20-year-old pine stands may also be attributed to differences in SOM quality. The alkyl C/O-alkyl C ratios were highest in the oldest stands, indicating that SOM in these stands was more resistant to further decomposition. Mechanized forest operations in radiata pine stands released at least 30 t C ha⁻¹ from the first 5 cm of the soil profile immediately after clearance, caused significant alterations in the soil structure, which lasted for a minimum of seven years, and also reduced the resistant C pool. As the Kyoto Protocol encourages forest management practices that potentially increase carbon sequestration, mechanical harvesting and site preparation in these steep slopes should be reconsidered.     

Local perceptions and regional climate trends on the Central Plateau of Burkina Faso

Due to devastating droughts in the 1970s and 1980s, climatic and environmental change in the West African Sahel has attracted a great deal of scientific research. While many of these studies documented a long‐term trend of declining rainfall, analyses conducted in the last few years suggest that a ‘recovery’ is underway. Drawing on ethnographic interviews, focus groups, and participant observation in two Provinces of the Central Plateau of Burkina Faso, we elicited local perspectives on these rainfall trends from the people who are most directly affected, namely local farmers. Fieldwork revealed that farmers in the research sites perceive that both overall seasonal rainfall and the number of ‘big rains’ during the rainy season have decreased over the last 30 years. We then tested these perceptions against rainfall records from nearby meteorological stations and found them to be corroborated. This paper illustrates how farmers of the Central Plateau now view drought as ‘normal’, having incorporated drought‐mitigation adaptations into their agricultural systems. Our case study highlights the need for ground truthing scientific analyses and assessing livelihood implications at the local level. It also advocates for sustained institutional support for rural communities, to increase their ability to adapt to climate change. Copyright © 2008 John Wiley & Sons, Ltd.     

Farmers' knowledge and perceptions of soil erosion and conservation measures in the Central Highlands,Kenya

A lack of appreciation of Kenyan farmers' knowledge and their perceptions of soil erosion and soil conservation measures was the reason for low adoption of recommended technologies. This research was carried out to identify the criteria that farmers used to distinguish farm‐types and to use these types to evaluate different knowledge levels and perceptions of soil erosion and existing soil and water conservation (SWC) measures in the Central Highlands of Kenya. Community meetings and semi‐structured household surveys were carried out in a small catchment, with 120 households. Results partly support the idea of using farmer‐developed criteria to distinguish among land managers with reference to a farm‐type classification. Criteria distinguishing three classes of land managers (good, moderate and poor) were significant with regard to the following land husbandry practices: use of hybrid or recycled seed and use of organic and/or inorganic fertilizers. Farmers were aware of on‐going soil erosion and of several erosion control measures. Whereas a majority of farmers preferred grass‐strips as a SWC measures, they did not recognize agroforestry as a form of SWC measure. Farmers perceived that SWC measures could successfully increase crop yields and soil‐water retention, and increase land value. In general, farmers did not perceive that SWC measures successfully prevented erosion phenomena, given the evidence of on‐site erosion indicators. They attributed the continued erosion to high rainfall, steep slopes, lack of maintenance and poorly designed SWC measures. They did not consider poor soil‐cover, up‐down tillage and tall trees to be the causes of erosion. Farmers faced several constraints in adopting SWC measures: lack of labour, tools, capital and know‐how to construct the measures. Copyright © 2005 John Wiley & Sons, Ltd.     

Soil sensitivity due to acid and heavy metal deposition in East Central Europe

Simultaneous soil acidification and deposition of heavy metals is a major concern for forest and agricultural soils of the Black Triangle region of East Central Europe including southern former East Germany, northern Bohemia of the Czech Republic, and southern Poland. The objective of this project was to develop historical and future projections of acid and heavy metal deposition to soils (As, Cd, Pb, Zn) and to produce a preliminary map of soil sensitivity to cadmium pollution and uptake by crops. Ultimately, we wish to assess the relative hazard and recovery times of soils to metals deposition in the region. Emission and deposition data bases obtained from several models developed at IIASA were linked using the Geographical Information System ARC/INFO to produce soil maps of sensitivity to cadmium mobility based on metals deposition, soil type, soil texture, organic matter content, and acid deposition. RAINS 6.1 (Alcamo et al., 1990) was utilized to produce maps of acid deposition for EMEP grids (150 km x 150 km). The largest amount of acid load is deposited in southern East Germany. Sulfur deposition in that area was 10–12 gS/m²/yr in 1990, and S+N deposition exceeded 8000 eq/ha/yr. But the hot spot for metals deposition is further to the east, in the Silesia area of southern Poland. The TRACE2 trajectory model of Alcamo, Bartnicki, and Olendrzynski (1992) was used to estimate cumulative metals deposition since 1955 with scenarios to 2010. Pb has improved over Europe since 1970 when depositions in the Ruhr River Valley of West Germany exceeded 60 mg/m²/yr. But cadmium deposition in southern Poland (Katowice and Krakow) has now accumulated to 60–70 mg/m² by atmospheric deposition alone. During base case simulations from 1955–87, approximately 1.8 mg/kg Pb and 0.12 mg/kg Cd have been added to the mixed plow-layer of 30 cm. If these emissions continue indefinitely, the accumulation of metals will become problematic for agriculture and the food chain.     

养鱼池塘机械拖网捕鱼系统的设计与试验

针对目前池塘拖网捕鱼作业完全靠人力,工作效率低的问题。通过在池塘两侧设置网具引导钢丝绳,利用液压绞车及拖引装置实现连续拖网的方法,开发了一套池塘机械拖网捕鱼系统。试验结果为：拖网系统在规格为50 m×100 m池塘进行机械拖网试验,拖网速度为10 m/min,拖网人员由12人减少至5人,拖网捕鱼效率约64.8%。机械拖网大幅减少了作业人数,运行稳定,适用于各类矩形池塘的捕捞作业。     

Texas entry-year agriculture teachers' perceptions, practices, and preparation regarding safety and health in agricultural education

The purpose of this study was to gather benchmark data for the assessment of the knowledge, attitudes, and perceptions regarding agricultural safety issues and curricula held by Texas agricultural teachers with less than two full years of teaching experience (entry-year teachers). Seventy-four of 118 well-distributed teachers responded to this survey. Researchers concluded that more females were entering a traditionally male-dominated field. Overall, teachers addressed safety within units of instruction rather than as separate units. The most useful forms of new teaching resources that this group of teachers would like to see produced were safety videos and study guides, and class demonstration/simulation activities. There was a significant difference in rankings between teachers less than 26 years old and teachers more than 26 years old regarding the usefulness of transparencies as a new teaching resource (F = 5.00, p = 0.0268). Few teachers were currently CPR and first aid certified, even though most had received training and completed a general safety and/or health related course while in college. Teachers generally agreed philosophically with most practices and exhibited personal beliefs consistent with proper safety preparedness and practice in agricultural settings. However, many of these teachers failed to practice what was expected of safe tractor operators, such as wearing safety belts and allowing younger drivers to operate the equipment.     

Microaggregates in red earths and related soils in East and Central Africa, their classification and occurrence

This paper describes the microaggregate structure of residual clay soils of the red earth order in East and Central Africa, examined by low-power microscopy, and the effects of gradual moistening and sudden wetting of the soil. Results showed a markedly angular microstructure termed fragmental, resulting from simple cleavages in the soil mass, a microgranular structure involving minute spherical bodies, either discrete or in small compound aggregates, and two types of intermediate structure. The several types of microaggregate and associated profile characteristics are described in detail, and are compared with those studied more recently in West Africa. The microgranular soils also contain larger pellet bodies originating as residual cores of rotted rock. Present evidence for the distribution of these soils is outlined and possible factors in their occurrence are reviewed, including age of land surface and termite activity.     

Soil loss in an olive grove in Central Spain under cover crops and tillage treatments,and farmer perceptions

Journal of Soils and Sediments - Soil erosion is a threat for the sustainability of the grove production all over the world, and olive groves are where the highest erosion is achieved. This study...     

中国中东部样区土壤、地形与耕地空间分布多样性特征

土壤、地形作为重要的自然因素,与耕地的关系密不可分。选取河南、江苏、浙江三省的9个典型样区作为研究对象,运用改进的仙农熵测度方法在3 km×3 km网格尺度下计算研究区的地学要素空间分布多样性特征。结果表明:(1)河南省样区的土类个数较其他地区丰富;如皋市、宁波市、诸暨市的土类具有单一性;开封市的土类空间分布特征最具波动性;多数样区土类的空间分布特征都具有相对稳定性。(2)研究区在平耕地以及浙江省的6°～15°下的缓坡耕地上地形的空间分布均匀度都在0.9以上,且耕地与地形坡度的相关强度与该特征具有相同规律。从地形类别来看,平原的空间分布特征最均匀,与耕地的相关性也最强。(3)随着时间变化,研究区耕地面积整体上呈减少趋势,但耕地的空间分布特征均匀度整体稳定。(4)在潮土和水稻土上,耕地的空间分布最均匀,且它们与耕地的关联性也相对最大,具有一致性特征。综上所述,土类和地形的空间分布特征具有复杂性,耕地的空间分布特征具有相对稳定性;研究区典型土类(如潮土、水稻土)、平耕地坡度(≤2°和2°～6°)、平原类别分别与耕地的空间分布格局具有较强的相关性。     

The influence of bark beetles outbreak vs. salvage logging on ground layer vegetation in Central European mountain spruce forests

Changes in the herb and moss layers of mountain spruce (Picea abies (L.) Karst.) forests after bark beetle (Ips typographus (L.)) outbreak were compared with and without forestry intervention. The study area is situated in the Šumava National Park (Czech Republic, Central Europe), where an extensive bark beetle outbreak occurred in the 1990s. Parts of forests were left without interventions, while salvage logging was applied in other areas. Altogether, 18 permanent research plots were established in: (1) climax stands with completely dead canopy, (2) climax stands where salvage logging was applied (clearcuts), and (3) waterlogged stands with only partly dead canopy. Vegetation composition of the ground layer and species numbers were evaluated in 1997 and 2002.The effect of salvage logging on vegetation was greater than that of the bark beetle outbreak itself. Forest herb species and partly also bryophytes survived relatively well under untouched dead canopy. The fewest changes occurred under the partly dead canopy in waterlogged forests. The herb layer expanded in clearcuts originated due to salvage logging, being dominated by grasses. Bryophytes were more susceptible to logging than herbs; their cover in clearcuts was markedly lower and composition changed towards pioneer species. The results show that a natural succession of mountain spruce forests after a bark beetle outbreak, if left without interventions, will probably avoid a pioneer stage and direct recovery of the forests will be possible. Salvage logging had negative effects on species composition of the spruce forests, delayed the forest recovery, and should not be permitted in the national park.     

马铃薯机械化收获除杂技术与装备研究进展

高效低损除杂是马铃薯机械化收获的核心环节,直接影响马铃薯的收获效率与收获品质,是助推马铃薯收获模式制定与收获装备研发与产业化进程的关键。由于不同马铃薯种植地区的自然环境等区域差异性较大,各地区马铃薯种植和收获模式复杂多变,因此对马铃薯机械化收获的除杂技术、装置结构和作业原理的需求各不相同。机械化收获除杂是减少生产成本、提高经济效益的重要方法,该研究基于国内马铃薯种植农艺,分析了国内外典型的马铃薯收获机基本结构和技术特点,对马铃薯机械化收获秧膜杂处理技术进行归纳总结,阐述薯土分离、薯秧分离、残膜回收及杂质清选等环节的装置结构与工作原理,对比分析不同除杂装置的特点与技术指标。针对国内覆膜种植、丘陵地区土壤粘重等特点,指出制约国内马铃薯除杂机械化发展的关键问题,并提出规范种植体系,研制适用机型与专用装备,农机农艺农信相融合和产学研相结合等建议,以期为马铃薯机械化收获除杂技术装备的研发应用奠定基础。     

主要粮食作物机械化生产工程模式构建与评价

中国主要粮食作物机械化生产已进入从单环节生产机械化向全程化发展的关键阶段,并在长期的发展过程中形成了多种工程模式。但目前鲜有研究从全程化、产业化、组织化、规模化的角度对其进行深入分析。因此,该文从系统工程的角度构建起主要粮食作物机械化生产工程模式体系框架。为了验证模式构建的合理性,客观分析不同模式的效果,该文在科学、实用、引导、可比、可行原则的基础上构建了一套评价指标体系。根据量化的难易程度,将指标分为易于量化的评价指标和不易量化的分析指标2种类型。评价指标以先进性、完备性、匹配度和经济性为评价准则,分析指标包括生态性、融合度、政策性和组织化指标。指标权重采用3轮专家匿名打分的方式获得,同时运用“现代农业发展目标与要求+统计数据分析+发达国家与地区经验+实际调查+专家咨询”相结合的方法得到指标标准值。在对全国不同区域采集数据进行评价的基础上,该文选取广西水稻机械化生产4种典型模式为例进行实例分析,从结果可以看出,该模式构建方法和评价指标体系具有较好的实用性,可推广应用并在实践中进一步完善。     

地质灾害易发山区群测群防体系与突发性灾害预警

地质灾害群测群防体系由县、乡、村3级监测网络、相关信息传输系统和必要的管理制度组成,并分别在县、乡、村建立地质灾害监测一级站(县监测中心(办公室))、二级站(乡监测组)和三级站(村监测网点),构成一个较完善的地质灾害群测群防体系和预警系统.以县群测群防办公室(一级站)为中心,以村群测群防监测网点(三级站)为基础,以市(地)、县相关专业人员为技术支撑,乡群测群防组(二级站)指导、督促检查村群测群防网点的工作,并起承上启下的协调工作.地质灾害临发预警分为一、二、三级警报,分别依据村级群测群防网点获得的监测、地面巡视和灾点临发前兆等资料,由县群测群防中心进行综合分析后作出,由县政府灾害防御中心发出警报.     

高校图书馆提高馆藏文献利用率的思考与实践

分析了高校图书馆文献利用率低的原因,并从建立科学的馆藏结构、提高馆员素质、加强宣传、建立完善专业的书评系统、实现联盟共建共享、推进馆际合作等,提出了改进的措施与建议。     

中国中、东部典型县域土壤与地表水体多样性的粒度效应及关联性

选取河南省和江苏省的6个典型县域作为研究区,在1 km×1 km网格尺度下采用空间粒度方法研究优势土属(DSF)和稀有土属(RSF)的土壤多样性值、3个研究时期空间分布面积指数(MSHDAI)和空间分布长度指数(MSHDLI)的粒度响应类型和4个指数间的关联性和相关关系的粒度响应及稳定性。结果表明:土壤DSF和RSF多样性值对空间粒度的响应基本上属于"无响应型",且RSF空间位置位于研究区边缘时随着粒度的增大而影响土壤多样性的稳定性;地表水体多样性MSHDAI和MSHDLI指数对粒度的响应均属于"下降型",二者间及二者平均值间的尺度效应关系为多项式函数时,拟合度最高;2000—2013年间,襄城县和吴江区土壤和地表水体多样性间的相关性类型为稳定型,二者相关关系的粒度效应有显著正、负相关两种,且相关性均未发生本质性变化,具有一定的稳定性。林县、固始县和溧水县为不稳定型,如皋市由于水网密度过大未表现出相关性。由此可知,研究区的地形、水体形态和密度及人类活动干扰等是影响土壤和地表水体多样性关系的主要因素。     

青海省机修梯田的试验推广及效益

<正> 青海省东部浅山地区,坡耕地水土流失严重,土质瘠薄,产量低而不稳,是制约农业发展的主要障碍。为了有效地控制水土流失,加快农田基本建设步伐,改变农业生产条件,增加粮食产量,自70年代以来,在组织人工修梯田的同时,开展了机械修梯田的试验研究和推广工作。     

黄土高塬地区机械化保护性耕作的回顾与展望

文章以近年来在陕西黄土高塬地区进行机械化保护性耕作的推广研究为基础,从正反两方面总结了在该地区推广保护性耕作的经验与教训,通过3年系列的试验数据表明,机械化保护性耕作对黄土高塬的生态环境建设、农业增产、农民增收起到积极作用.     

Reduced-impact logging and temporal activity of understorey bats in lowland Amazonia

Because global timber demands continue to threaten tropical rain forests, identification of sustainable-use forest management protocols that meet human needs while preserving biodiversity is critical. Reduced-impact logging (RIL) protocols are increasingly common in the tropics and may be a viable option for sustainable forest use; however, few studies have documented faunal responses to RIL. Moreover, evaluations of abundance or diversity may not be sufficient for a comprehensive understanding of faunal responses to human activities, especially in the short-term. We assessed the effects of RIL on the temporal activity patterns of abundant bats in lowland Amazonian rain forest. More specifically, we characterized temporal patterns of activity, overlap of temporal activity, and dispersion of activity modes for seven abundant bat species and for four common bat guilds in RIL forest and in undisturbed forest in Tapajós National Forest, Pará, Brazil. Temporal activity of aerial insectivores, nectarivores, and gleaning animalivores did not change in response to RIL. In contrast, three of five species of frugivores and frugivores as a group changed their patterns of temporal activity in response to RIL. RIL had a greater effect on temporal activity of frugivores that foraged in the understorey than on frugivores that foraged in multiple forest strata. Overlap of temporal activity of frugivores was greater than expected by chance in undisturbed forest, but was random in RIL forest. Changes in activity may be a response to a combination of increased predation risk and reduced distances of early evening flights between day roosts and feeding areas in RIL forest compared to undisturbed forest.