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1.
There are few reliable data sets to inspire confidence in policymakers that soil organic carbon (SOC) can be measured on farms. We worked with farmers in the Tamar Valley region of southwest England to select sampling sites under similar conditions (soil type, aspect and slope) and management types. Topsoils (2–15 cm) were sampled in autumn 2015, and percentage soil organic matter (%SOM) was determined by loss on ignition and used to calculate %SOC. We also used the stability of macroaggregates in cold water (WSA) (‘soil slaking’) as a measure of ‘soil health’ and investigated its relationship with SOC in the clay‐rich soils. %SOM was significantly different between management types in the order woodland (11.1%) = permanent pasture (9.5%) > ley‐arable rotation (7.7%) = arable (7.3%). This related directly to SOC stocks that were larger in fields under permanent pasture and woodland compared with those under arable or ley‐arable rotation whether corrected for clay content (F = 8.500, p < .0001) or not (F = 8.516, p < .0001). WSA scores were strongly correlated with SOC content whether corrected for clay content (SOCadj R2 = .571, p < .0001) or not (SOCunadj R2 = 0.490, p = .002). Time since tillage controlled SOC stocks and WSA scores, accounting for 75.5% and 51.3% of the total variation, respectively. We conclude that (1) SOC can be reliably measured in farmed soils using accepted protocols and related to land management and (2) WSA scores can be rapidly measured in clay soils and related to SOC stocks and soil management.  相似文献   
2.
食用菌富含膳食纤维、矿物质、微量元素、维生素和多种氨基酸,是多功能理想食物。尽管食用菌脂类物质含量较低,但包含人类必需的不饱和脂肪酸,如亚油酸、油酸和亚麻酸等。通过对食用菌脂类物质研究成果进行总结,尤其是不饱和脂肪酸种类、含量及其开发利用,以期为食用菌的资源开发提供参考。  相似文献   
3.
为探究健康意识对规模养殖户以使用环保饲料为代表的亲环境行为的作用,以湖北省402个生猪规模养殖户为研究对象,应用Heckman两阶段模型,探讨健康意识对不同群体规模养殖户的影响差异。研究结果表明,大多数规模养殖户(78.97%)愿意为环保饲料付费,且平均意愿支付水平为每头生猪饲料成本的6.69%(46.80元·头-1)。健康意识中的健康关注程度对生猪规模养殖户环保饲料支付意愿具有正向促进作用,健康变化感知对其意愿支付水平的影响正向显著。通过主成分分析,健康意识整体上直接对规模养殖户环保饲料的支付意愿与意愿支付水平产生正向影响。而差异性分析也表明,在环保饲料支付意愿决策上,健康意识不同的规模养殖户群体间有明显差异。  相似文献   
4.
国家相关管理部门联合提出按照“环境优良、服务优质、管理完善、特色鲜明、效益明显”的要求建设一批国家森林康养基地。以浙江千岛湖龙川湾为例,分析其森林资源、地理区位、产业链、发展规模、社会合作、管理保障、三大效益等方面建设森林康养基地的优势,整合提升游憩观赏、研学文化、垂钓休闲、扶犁耕地、康养保健、疗养康复、健身拓展区域空间布局与发展举措,从康养体验、休闲体验、运动健身等方面增强千岛湖龙川湾森林康养基地功能,推进森林康养产业发展。  相似文献   
5.
阐述了森林健康理念和森林康养的基本概念,介绍了森林健康理念和森林康养的发展现状,分析了森林健康与森林康养产业之间的关系。结果表明:森林康养产业的理论基础就是基于森林健康理念继承发展来的,必然会促进森林健康产业的发展。运用森林健康理念指导森林康养产业发展是森林康养产业可持续发展的有效途径,森林健康理念在中国会不断完善和发展,也更有利于中国森林康养产业的发展。展望康养产业,会形成一种新的经济形态,成为国民福祉。  相似文献   
6.
Integrated crop–livestock–forest is a promising strategy to improve soil quality. It comprises four different integrated farming systems: crop–livestock, crop–forest, forest–livestock and crop–livestock–forest. This work systematically reviewed studies about integrated crop–livestock–forest systems and soil quality. A total of 92 papers were retrieved from the Web of Science—Clarivate Analytics platform, and the following information was analysed: publication year, institution, region of the studied site, type of integrated system, soil type, tillage system, maximum soil depth and the soil quality indicators assessed. Most studies were published in the second half of the 2010s. Brazil is a prominent focus of research about soil quality and integrated crop–livestock–forest systems, with significant contribution from its central and southern regions. The Embrapa was the main publishing institution, present in over one‐third of the studies. Crop–livestock was the most common integrated system, Ferralsols was the most common soil group, and most of the studied soils were clayey. No tillage was the main tillage system. Most studies focused on the topsoil, assessing physical and/or chemical soil quality indicators. More emphasis on biological indicators of soil quality is required, as well as assessments integrating biological, physical and chemical indicators of soil quality. Future works should compare different integrated systems, including assessments deeper in the soil profile, especially in systems with the forest component, and also in sandy and silty soils. Soil quality indicators that have been rarely used should be further tested. Novel indicators should be added to better understand the promotion of soil quality by integrated crop–livestock–forest systems.  相似文献   
7.
为了对广西某规模化食蟹猴养殖场饮用水和青饲料卫生质量情况进行监测,对饮用水和青饲料进行连续抽样监测,按照《生活饮用水卫生标准》《生活饮用水卫生标准检验方法》和《国家禁用和限用的农药名单》进行检测与评价。结果显示:抽取6份饮用水样检测26项理化指标,有3份不合格,超标率达50.0%,超标指标有浑浊度、肉眼可见物;抽取147份饮用水检测微生物指标,有22份超标,超标率达15.0%,超标微生物指标为细菌总数、总大肠菌群、耐热大肠菌群和大肠埃希氏菌;抽取13个品种青饲料48份检测10种禁用农药残留情况,甲胺磷、敌敌畏、乐果、氧化乐果、氰戊菊脂、多菌灵、啶虫脒、吡虫啉、三唑磷、毒死蜱检出率分别为2.1%、0、0、0、0、12.5%、2.1%、12.5%、2.1%、2.1%。说明该规模化食蟹猴养殖场饮用水存在不合格情况,青饲料检出农药残留。  相似文献   
8.
Atlantic salmon (Salmo salar) were fed five graded levels of eicosapentaenoic acid (EPA, 20:5n‐3) and docosahexaenoic acid (DHA, 22:6n‐3), from 1.4 to 5.2% of total fatty acids (FA, 5–17 mg kg?1 feed), and grew from ~160 g to ~3000 g, with the period from 1450 g onwards conducted both at 6 °C and at 12 °C. All fish appeared healthy, and there were no diet‐related differences in haematological or plasma parameters, as well as intestinal histological or gut microbiota analysis. Fish reared at 6 °C had higher accumulation of storage lipids in the liver compared to fish reared at 12 °C. Liver lipids also increased with decreasing dietary EPA + DHA at 6 °C, while there was no such relationship at 12 °C. Gene expression of SREBP1 and 2, LXR, FAS and CPT1 could not explain the differences in liver lipid accumulation. In liver polar lipids, DHA was found to be reduced when dietary EPA + DHA was <2.7% of FAs, while the level of EPA in the membranes was not affected. In conclusion, reducing dietary EPA + DHA from 5.2 to 1.4% of total FAs had a minor impact on fish health. Temperature was the factor that most affected the liver lipid accumulation, but there was also an interaction with dietary components.  相似文献   
9.
基于健康差异视角,利用福建省农村老年人住院服务利用调研数据,采用日常生活自理能力、工具性日常生活活动能力和认知能力3个指标来评定农村老年人健康状况,并在此基础上通过聚类分析法将农村老人的健康状况分为3个等级,然后再运用两部模型重点考察新型农村合作医疗补偿机制对不同健康水平农村老人住院服务利用的影响及差异。结果表明:乡级医疗机构的报销补偿对农村老人就医选择的影响不存在健康差异,但是高级别医院的报销补偿与补偿封顶线对健康较差的老人的影响更大。另外,新农合补偿机制中乡级医院报销比例与补偿封顶线的提高对老人住院支出有显著影响,且乡级医疗机构报销倾斜对所有健康等级老人的住院医疗支出都有显著影响。  相似文献   
10.
为掌握典型药物在农作物中的污染特征及健康风险,保障农产品质量安全,利用超声萃取-固相萃取-高效液相色谱/串联质谱(LC-MS/MS)技术,对围场县全县马铃薯中5大类(磺胺类、四环素类、氟喹诺酮类、大环内酯类及其他类)25种药物污染水平及富集效果进行了调查,并对健康风险进行了评价。结果表明,有20种目标物被检出,不同目标物检出率差异显著,检出含量范围为0.13~3.67μg·kg-1,单种污染物最高检出含量为17.0μg·kg-1。马铃薯对目标污染物的富集系数范围在0.01~39.6之间,最大富集系数为61.8。畜禽粪便是马铃薯中药物残留的主要来源,尽管整体检出水平和健康风险相对较低,但长期摄入与协同作用引发的潜在健康风险不容忽视。因此,仍需严控污染源头,推进畜禽粪便安全资源化利用,确保农田环境质量及农产品安全品质。  相似文献   
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