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101.
好氧堆肥及蚯蚓堆肥是对畜禽粪便进行肥料化处置的有效方式,但畜禽粪便中残留的不同浓度四环素对二者堆肥过程的影响是否相同却并不清楚.因此,将不同浓度(5、25、125 mg·kg-1)的四环素添加到牛粪-秸秆物料中,对比了好氧堆肥与蚯蚓堆肥堆制过程中堆体腐熟度指标的变化、堆肥产品养分含量的区别以及堆肥产品中四环素去除效率的差异,以期为不同浓度四环素的畜禽粪便肥料化提供适宜的处置方法 .研究结果显示,高浓度(125 mg·kg-1)四环素添加延缓了好氧堆肥的升温进程,但与低浓度(5、25 mg·kg-1)四环素添加处理相比并未显著影响堆体的腐熟度指标、堆肥产品总养分含量及速效养分含量.高浓度(125 mg·kg-1)四环素添加导致了蚯蚓堆肥中蚯蚓密度和生物量的显著下降,并导致蚯蚓堆肥无法正常启动.在蚯蚓堆肥中,低浓度(5、25 mg·kg-1)四环素添加处理之间在堆体的腐熟度指标,堆肥产品总养分含量及速效养分含量方面无显著差异.好氧堆肥对畜禽粪便中四环素的去除率可达90%以上,显著高... 相似文献
102.
本文从央地纵向关系、部门间横向关系、环保督察斜线关系等视角出发,探讨畜禽养殖废弃物治理政策背后的府际关系博弈逻辑和利益融合路径,实证探讨治理案例。结果表明,政府府际间存在利益博弈,但可以实现利益融合和治理有效。其中,经济、社会和生态利益的排序差异、治理事务权与财权不匹配、地方考核指标偏向经济等因素造成央地间利益诉求差异,可从增加融资渠道、优化考核方式、扩大监管渠道和多元共治等方面促进利益融合;双重管理体制、全局和局部利益并存等因素造成同一层级的不同政府部门间存在利益诉求差异,但环保督察等“运动式”治理、约束性生态指标被纳入官员考核体系等措施有助于其组成政绩共荣体;结合案例实证检验,提出中央政府需要通过严格制度安排和多重监管督察治理动态、整合地方政策资源帮助政府各部门间形成政绩共荣体、疏堵并举精准施策构建紧密利益联结机制、搭建“政府—市场—公众”多元共治治理格局等政策建议。 相似文献
103.
104.
区域农田畜禽承载量预测模型构建与应用:以赤峰市为例 总被引:3,自引:0,他引:3
为对区域现有生猪养殖数量的合理性进行评价及对生猪养殖承载量进行预测,从畜禽养殖-耕地-作物系统出发,基于农田养分平衡理论及有机和无机肥合理配施方法,构建区域农田畜禽承载量预测模型。以赤峰市为例,设定有机和无机肥配施比例为5∶5,并保持现有农田N或P2O5养分盈余量不变,分别基于N和P2O5养分盈余量不变实地应用该模型。结果表明,基于N时可新增生猪养殖数量43.6万头,承载量为630.8万头;基于P2O5时可新增生猪养殖数量369.3万头,承载量为1 041.3万头。位于西拉木伦河南岸的松山区、翁牛特旗、喀喇沁旗、宁城县和敖汉旗是可新增生猪养殖的主要区域。从环境压力角度考虑,推荐基于N的预测值作为计算赤峰市可新增生猪养殖量和承载量的依据。 相似文献
105.
Participatory epidemiology methods were employed retrospectively in three pastoralist regions of Ethiopia to estimate the specific causes of excess livestock mortality during drought. The results showed that starvation/dehydration accounted for between 61.5 and 100 per cent of excess livestock mortality during drought, whereas disease‐related mortality accounted for between 0 and 28.1 per cent of excess mortality. Field observations indicate that, in livestock, disease risks and mortality increase in the immediate post‐drought period, during rain. The design of livelihoods‐based drought response programmes should include protection of core livestock assets, and it should take account of the specific causes of excess livestock mortality during drought and immediately afterwards. This study shows that, when comparing livestock feed supplementation and veterinary support, relatively more aid should be directed at the former if the objective is to protect core livestock during drought. Veterinary support should consider disease‐related mortality in the immediate post‐drought period, and tailor inputs accordingly. 相似文献
106.
Animals in the Himalayan region are reared basically to supplement the family income and sustain crop production, and constitute an important component of the rural economy of the region. Given the ecological importance of the livestock production system in terms of intrinsic values as a life support system for local people and a contribution towards sustainable agriculture through its role in the maintenance of soil fertility, the present study was conducted. This paper describes and assesses the current status of livestock production systems, monetary input/output, status of available forest resources, current level of pressure on the livestock production system and recommends strategies for sustainable development of a livestock production system in the Rawain Valley of Central Himalaya. 相似文献
107.
Abstract: Riparian and quaking aspen (Populus tremuloides) woodlands are centers of avian abundance and diversity in the western United States, but they have been affected adversely by land use practices, particularly livestock grazing. In 1990, cattle were removed from a 112,500‐ha national wildlife refuge in southeastern Oregon. Thereafter, we monitored changes in vegetation and bird abundance in years 1–3 (phase 1) and 10–12 (phase 2) in 17 riparian and 9 snow‐pocket aspen plots. On each 1.5‐ha plot, we sampled vegetation in 6 transects. Three times during each breeding season, observers recorded all birds 50 m to each side of the plot's 150‐m centerline for 25 minutes. We analyzed data with multivariate analysis of variance and paired t tests with p values adjusted for multiple comparisons. In both periods, riparian and snow‐pocket aspen produced extensive regeneration of new shoots ( stems/ha and 7079 stems/ha, respectively). By phase 2, a 64% increase in medium‐diameter trees in riparian stands indicated successful recruitment into the overstory, but this pattern was not seen in snow‐pocket stands, where the density of trees was over 2 times greater. By phase 2 in riparian and snow‐pocket stands, native forb cover had increased by 68% and 57%, respectively, mesic shrub cover had increased by 29% and 58%, and sagebrush cover had decreased by 24% and 31%. Total avian abundance increased by 33% and 39% in riparian and snow‐pocket aspen, respectively, ground or understory nesters increased by 133% and 67% and overstory nesters increased by 34% and 33%. Similarly, ground or understory foragers increased by 25% and 32%, aerial foragers by 55% and 57%, and overstory foragers by 66% and 43%. We interpreted the substantial regeneration of aspen shoots, increased densities of riparian forbs and shrubs, and increased avian abundances as a multitrophic‐level response to the total removal of livestock and as substantial movement toward recovery of biological integrity. 相似文献
108.
畜禽养殖业污染状况及管理对策 总被引:8,自引:0,他引:8
分析了畜禽养殖业对农村环境污染的严重性,阐述了畜禽粪便的综合利用途径,提出了防止畜禽养殖污染的管理对策和措施。 相似文献
109.
以规模化畜禽养殖业为调查对象,主要调查统计了蛋鸡、肉鸡、猪、肉牛、奶牛、羊。根据调查和数据统计,掌握了鞍山市规模化畜禽养殖业的特点及规模化畜禽养殖业污染物的排放量,并以此提出了污染防治对策。 相似文献
110.
中国畜牧业全生命周期温室气体排放时空特征分析 总被引:8,自引:0,他引:8
运用生命周期评价方法,选取家畜胃肠道发酵、粪便管理系统、畜禽饲养环节耗能、饲料粮种植、饲料粮运输加工和畜禽产品屠宰加工6大环节,采用面板数据测算和分析1990~2011年中国及2011年国内各地区畜牧业温室气体排放特征.研究表明,22年间,中国畜牧业全生命周期及各个环节的CO2当量排放量均呈现上升趋势,尤其是畜禽饲养耗能、饲料粮种植、饲料粮运输加工和畜禽屠宰加工环节的增长更为显著,但历年饲料粮运输加工和畜禽屠宰加工环节占畜牧业全生命周期CO2当量排放总量的比重均低于1%和0.05%;家畜胃肠道发酵和粪便管理系统环节占畜牧业全生命周期CO2当量排放总量的比重呈下降趋势;22年间,反刍家畜的CO2当量排放量占55.25%,非反刍畜禽占44.75%.2011年,国内省域间内蒙古、辽宁和云南的畜牧业全生命周期CO2排放当量和排放强度均位居全国前10位;西部地区畜牧业全生命周期CO2当量排放量所占比重最大,并且西部地区的排放强度最高;农区畜牧业全生命周期CO2当量排放量占63.88%,牧区占14.07%,但牧区的排放强度最高,农区最低. 相似文献