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我国草地的固碳功能

高树琴,赵霞,方精云

《中国工程科学》 2016年 第18卷 第1期   页码 73-79 doi: 10.15302/J-SSCAE-2016.01.010

摘要：

本文通过综述当前我国草地碳库的研究成果，并利用1982—2011年的遥感影像，估算出我国草地生态系统碳库约为31.2 PgC，其中96 %储存于土壤中。由于我国草地类型多样，分布地域广阔，造成草地植被碳密度分布的空间异质性很高。内蒙古是草地植被碳库最大的省份，其次是西藏和青海，六大牧区的植被碳库占全国草地植被碳库总量的71 %。然而，我国90 %的天然草地发生不同程度的退化，采取有效的人工管理措施和实施重大的生态建设工程，均对草地碳库的恢复具有明显的作用，说明我国草地有很大的碳汇潜力。

关键词： 草地     植被碳储量     土壤碳储量     草地退化     固碳潜力    

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Using balance of seasonal herbage supply and demand to inform sustainable grassland management on the

Xinquan ZHAO, Liang ZHAO, Qi LI, Huai CHEN, Huakun ZHOU, Shixiao XU, Quanmin DONG, Gaolin WU, Yixin HE

《农业科学与工程前沿（英文）》 2018年 第5卷 第1期   页码 1-8 doi: 10.15302/J-FASE-2018203

摘要： To mitigate the impacts of grassland degradation on the Qinghai–Tibetan Plateau (QTP), in recent decades China has been implementing large-scale conservation programs and has invested about 42 billion CNY (7 billion USD). However, these programs are faced with major challenges involving trade-offs between ecological function, livestock production and income of pastoralists. Scientific assessments, as well as technical and policy issues, have not fully captured the complex ecological, social and economic dynamics of the challenges facing grassland management on the QTP. Pastoral livestock production on the QTP is characterized by imbalance in both quality and quantity between livestock seasonal nutrient requirements and herbage production, which forces pastoralists to keep larger numbers of livestock for longer periods, leading to overgrazing. To solve these problems, an integrated crop-livestock system is promoted to improve the efficiency of livestock production and conserve natural grassland as well for a sustainable system for the QTP.

关键词： ecosystem function     grassland degradation     grassland management     integrated rangeland-cropland-livestock production system     Qinghai–Tibetan Plateau    

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INTENSIFICATION OF GRASSLAND-BASED DAIRY PRODUCTION AND ITS IMPACTS ON LAND, NITROGEN AND PHOSPHORUS

《农业科学与工程前沿（英文）》 2021年 第8卷 第1期

摘要：

• Monitoring data of>5000 dairy farms collected and examined in uniform manner.

• Environmental performances of farms influenced by government regulations.

• N and P surpluses at farm level remained about constant with intensity level.

• N and P use efficiencies at farm, herd and soil increased with intensity level.

• Accounting for externalization of off-farm feed production affects NUE and PUE.

• Ammonia emissions per kg milk decreased with the level of intensification.

 

Many grassland-based dairy farms are intensifying production, i.e., produce more milk per ha of land in response to the increasing demand for milk (by about 2% per year) in a globalized market. However, intensive dairy farming has been implicated for its resources use, ammonia and greenhouse gas emissions, and eutrophication impacts. This paper addresses the question of how the intensity of dairy production relates to N and P surpluses and use efficiencies on farms subjected to agri-environmental regulations. Detailed monitoring data were analyzed from 2858 grassland-based dairy farms in The Netherlands for the year 2015. The farms produced on average 925 Mg·yr−1 milk. Milk production per ha ranged from<10 to>30 Mg·ha−1·yr−1. Purchased feed and manure export strongly increased with the level of intensification. Surpluses of N and P at farm level remained constant and ammonia emissions per kg milk decreased with the level of intensification. In conclusion, N and P surpluses did not differ much among dairy farms greatly differing in intensity due to legal N and P application limits and obligatory export of manure surpluses to other farms. Further, N and P use efficiencies also did not differ among dairy farms differing in intensity provided the externalization of feed production was accounted for. This paper provides lessons for proper monitoring and control of N and P cycling in dairy farming.

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保障我国草地生态与食物安全的战略和政策

“中国草地生态保障与食物安全战略研究”项目组

《中国工程科学》 2016年 第18卷 第1期   页码 8-16 doi: 10.15302/J-SSCAE-2016.01.002

摘要：

草地是我国面积最大的陆地生态系统，在保障国家生态安全、食物安全和弘扬中华草原文明中具有突出的战略地位。本文分析了我国草地资源、草地生态功能、生产力的现状和变动趋势及其主要的影响因素，阐述了目前和未来我国草地生态保障、草地生产力和草牧业发展面临的机遇、挑战和潜力。在以上内容分析的基础上，提出了我国保障草地生态安全和发展草牧业的战略目标、战略重点、关键措施和主要政策建议。

关键词： 草地     生态保障     食物安全     发展战略     政策建议    

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GRASSLAND AGRICULTURE IN CHINA—A REVIEW

《农业科学与工程前沿（英文）》 2021年 第8卷 第1期   页码 35-44

摘要：

• Grassland-based livestock production systems cover large areas in China.

• China is facing degradation of rangeland and has great shortage of forage.

• Five types of mixed crop-livestock systems in China described.

• Improving crop–livestock integration requires S&T and policy supports.

 

Interactions between crops and livestock have been at the core of the evolution of many agricultural systems. In this paper, we review the development and characteristics of mixed crop-livestock systems, with a focus on grassland-based systems, as these cover large areas in China, and face several challenges. Following the transition from the original hunting and foraging systems to a sedentary lifestyle with integrated crop-livestock production systems some 8000 years ago, a range of different mixed systems have developed, depending on rainfall, solar radiation and temperature, culture and markets. We describe 5 main types of integrated systems, (1) livestock and rangeland, (2) livestock and grain production, (3) livestock and crop – grassland rotations, (4) livestock, crops and forest (silvo-pasture), and (5) livestock, crops and fish ponds. Next, two of these mixed systems are described in greater detail, i.e., the mountain-oasis-desert system and its modifications in arid and semi-arid regions, and the integrated crop-livestock production systems on the Loess Plateau. In general, crop-livestock interactions in integrated systems have significant positive effects on crop production, livestock production, energy use efficiency and economic profitability. We conclude that improved integration of crop-livestock production systems is one of the most important ways for achieving a more sustainable development of animal agriculture in China.

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INTENSIFICATION OF GRASSLAND-BASED DAIRY PRODUCTION AND ITS IMPACTS ON LAND, NITROGEN AND PHOSPHORUS

Jouke OENEMA, Oene OENEMA

《农业科学与工程前沿（英文）》 2021年 第8卷 第1期   页码 130-147 doi: 10.15302/J-FASE-2020376

摘要： Many grassland-based dairy farms are intensifying production, i.e., produce more milk per ha of land in response to the increasing demand for milk (by about 2% per year) in a globalized market. However, intensive dairy farming has been implicated for its resources use, ammonia and greenhouse gas emissions, and eutrophication impacts. This paper addresses the question of how the intensity of dairy production relates to N and P surpluses and use efficiencies on farms subjected to agri-environmental regulations. Detailed monitoring data were analyzed from 2858 grassland-based dairy farms in The Netherlands for the year 2015. The farms produced on average 925 Mg·yr milk. Milk production per ha ranged from<10 to>30 Mg·ha ·yr . Purchased feed and manure export strongly increased with the level of intensification. Surpluses of N and P at farm level remained constant and ammonia emissions per kg milk decreased with the level of intensification. In conclusion, N and P surpluses did not differ much among dairy farms greatly differing in intensity due to legal N and P application limits and obligatory export of manure surpluses to other farms. Further, N and P use efficiencies also did not differ among dairy farms differing in intensity provided the externalization of feed production was accounted for. This paper provides lessons for proper monitoring and control of N and P cycling in dairy farming.

关键词： ammonia     externalization     feed     forage maize     front runners     manure production     milk yield     nitrogen surplus    

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Allocation of grassland, livestock and arable based on the spatial and temporal analysis for food demand

Huilong LIN, Ruichao LI, Yifan LIU, Jingrong ZHANG, Jizhou REN

《农业科学与工程前沿（英文）》 2017年 第4卷 第1期   页码 69-80 doi: 10.15302/J-FASE-2017140

摘要： To explore the distribution of food demand and the projected trend in future food demand in China, this paper analyzed the change in current (1998–2012) per-capita demand for grain, grain-consuming and herbivorous livestock products, and predicted the food demand in 2020. The results indicated that in 1998–2012, the national per-capita consumption of grain ration declined by about 36.66%, and the per-capita consumption of grain-consu-ming and herbivorous livestock products increased by about 48% and 34.09%, respectively. The grain-consu-ming livestock products have become the primary source of both calories and protein for consumers. The proportion of herbivorous livestock products in consumer diets has increased steadily and there has been huge potential in substituting beef and mutton for pork in this dynamic market. The demand for food in different provinces of China is highly variable, which is important for planning grassland agriculture development and ensuring food safety. The demand for grain, and grain-consuming and herbivorous livestock products will increase by about 3.3%, 20% and 14% respectively by 2020. Based on the food demand and trend in the development of grassland agriculture, the 31 provinces in China are divided into three priority groups for grassland agriculture development.

关键词： arable land equivalent unit (ALEU)     food equivalent unit (FEU)     food security     grassland agriculture     time trend prediction    

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Influence of construction-induced damage on the degradation of freeze–thawed lightweight cellular concrete

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 781-792 doi: 10.1007/s11709-021-0733-9

摘要： During the construction of lightweight cellular concrete (LCC), material damage frequently occurs, causing the degradation and deterioration of the mechanical performance, durability, and subgrade quality of LCC. The construction-induced damage can be more significant than those from the service environment of LCC, such as freeze–thaw (F–T) action in cold regions. However, the effect of construction-induced damage on LCC during F–T cycles is often ignored and the deterioration mechanisms are not yet clarified. In this study, we investigated the factors causing damage during construction using a sample preparation method established to simulate the damage in the laboratory setting. We conducted F–T cycle tests and microstructural characterization to study the effect of microstructural damage on the overall strength of LCC with different water contents under F–T actions. We established the relationship between the pore-area ratio and F–T cycle times, pore-area ratio, and strength, as well as the F–T cycle times and strength under different damage forms. The damage evolution is provided with the rationality of the damage equation, verified by comparing the measured and predicted damage variables. This study would serve as a guide for the construction and performance of LCC in cold regions.

关键词： lightweight cellular concrete     construction-induced damage     freeze-thaw action     microstructure     degradation mechanism    

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Grassland management practices in Chinese steppes impact productivity, diversity and the relationship

Yingjun ZHANG, Wenjie LU, Hao ZHANG, Jiqiong ZHOU, Yue SHEN

《农业科学与工程前沿（英文）》 2018年 第5卷 第1期   页码 57-63 doi: 10.15302/J-FASE-2017192

摘要： Grasslands are crucial parts of the terrestrial ecosystem, with an extremely high differentiation of productivity and diversity across spatial scales and land use patterns. The practices employed to manage grassland, such as grazing, haymaking, fertilization or reseeding, can improve the grassland condition. This study focuses on the changes in productivity and diversity and the relationship between them as affected by management practices. Productivity and diversity have unequivocally been altered in response to different management practices. When grazing intensity of a typical steppe increased from 1.5 to 9 sheep per hectare, both productivity and diversity declined. Higher grazing intensity (6 to 9 sheep per hectare) accelerated loss of diversity because of lower productivity. Productivity was significantly improved but diversity was lost by fertilizing. N fertilization also reduced the sensitivity of diversity to productivity. A similar response was found in mown grassland with increased productivity and diversity but their relationship was negatively affected. Mowing also slowed down the decline in diversity as productivity increased. Reseeding purple-flowered alfalfa led to an increased diversity, while yellow-flowered alfalfa increased productivity significantly. The negative productivity-diversity relationship was transformed to a positive one by reseeding alfalfa. These results enhance understanding of how productivity, diversity and their relationships change in response to altered grassland management practices, and support an integrated approach for improving both productivity and diversity.

关键词： diversity     fertilizing     grassland management practice     grazing     mowing     productivity     reseeding    

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Efficient degradation of orange II by ZnMn

Qingzhuo Ni, Hao Cheng, Jianfeng Ma, Yong Kong, Sridhar Komarneni

《化学科学与工程前沿（英文）》 2020年 第14卷 第6期   页码 956-966 doi: 10.1007/s11705-019-1907-z

摘要： A ZnMn O catalyst has been synthesized via a sucrose-aided combustion method and characterized by various analytical techniques. It is composed of numerous nanoparticles (15–110 nm) assembled into a porous structure with a specific surface area (SSA) of 19.1 m ·g . Its catalytic activity has been investigated for the degradation of orange II dye using three different systems, i.e., the photocatalysis system with visible light, the chemocatalysis system with bisulfite, and the photo-chemical catalysis system with both visible light and bisulfite. The last system exhibits the maximum degradation efficiency of 90%, much higher than the photocatalysis system (15%) and the chemocatalysis system (67%). The recycling experiments indicate that the ZnMn O catalyst has high stability and reusability and is thus a green and eximious catalyst. Furthermore, the potential degradation mechanisms applicable to the three systems are discussed with relevant theoretical analysis and scavenging experiments for radicals. The active species such as Mn(III), O , h , e , SO and HO are proposed to be responsible for the excellent degradation results in the photo-chemical catalysis system with the ZnMn O catalyst.

关键词： ZnMn2O4     photo-chemical catalysis     bisulfite     dye degradation    

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Promotive effect of pyridine on indole degradation by activated sludge under anoxic conditions

LI Yongmei, GU Guowei, LI Wenshu

《环境科学与工程前沿（英文）》 2007年 第1卷 第4期   页码 493-497 doi: 10.1007/s11783-007-0079-0

摘要： Batch experiments were carried out to investigate the promotive effect of pyridine on indole degradation under denitrifying conditions. The seed sludge was obtained from a local coal-coking wastewater treatment facility and was acc

关键词： wastewater treatment     coal-coking wastewater     promotive     degradation    

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anchored alginate/poly(acrylic acid/acrylamide) double-network hydrogel composites for efficient catalytic degradation

《化学科学与工程前沿（英文）》 2023年 第17卷 第7期   页码 893-905 doi: 10.1007/s11705-022-2290-8

摘要： A novel alginate/poly(acrylic acid/acrylamide) double-network hydrogel composite with silver nanoparticles was successfully fabricated using the sol–gel method. The presence of carboxyl and amide groups in the network structure provided abundant active sites for complexing silver ions, facilitating the in situ reduction and confinement of silver nanoparticles. In batch experiments, the optimal silver loading was 20%, and 5 mmol·L–1 of p-nitrophenol was completely degraded in 113 s with a rate constant value of 4.057 × 10−2 s–1. In the tap water system and simulated seawater system, the degradation time of p-nitrophenol at the same concentration was 261 and 276 s, respectively, with a conversion rate above 99%. In the fixed-bed experiment, the conversion rate remained above 74% after 3 h at a flowing rate of 7 mL·min–1. After 8 cycling tests, the conversion rate remained at 98.7%. Moreover, the catalyst exhibited outstanding performance in the degradation experiment of four typical organic dyes.

关键词： double-network hydrogel     dye degradation     silver nanoparticles     alginate    

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Sustainable wood-based nanotechnologies for photocatalytic degradation of organic contaminants in aquatic

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1346-6

摘要：

•Wood and its reassemblies are ideal substrates to develop novel photocatalysts.

关键词： Wood     Nanocatalysts     Photodegradation     Organic contaminants     Composites    

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藏北高原草地生态治理与畜牧业协同发展模式研究

干珠扎布,胡国铮,高清竹,江村旺扎,旦久罗布,参木友,巴桑旺堆,杨富裕,魏学红,杨永平

《中国工程科学》 2019年 第21卷 第5期   页码 93-98 doi: 10.15302/J-SSCAE-2019.05.013

摘要：

藏北高原是我国重要的生态安全屏障和高原特色畜牧业基地，而高寒草地退化严重制约着其生态和生产功能，给生态保护和畜牧业发展带来了挑战。本文在深入分析藏北高原生态治理与畜牧业发展状况的基础上，探讨了藏北高寒草地生态与生产功能的主要影响因素，提出了藏北高原草地生态治理与畜牧业协同发展的模式体系。研究表明，通过草地生态恢复、优化放牧管理方式、人工牧草种植、低海拔农区种草高海拔牧区养畜的“低草高牧”模式、冬季半舍饲养殖等一系列措施，能够推进高寒草地生态功能提升、促进草地畜牧业转型升级，实现“保护中发展”与“发展中保护”。相关研究将为治边稳藏、保障国家生态安全、增加牧民收入提供战略引导和科技支撑。

关键词： 藏北高原     生态修复     草地畜牧业     协同发展    

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Thermal degradation kinetics and lifetime estimation for polycarbonate/polymethylphenylsilsesquioxane

Jiangbo WANG, Zhong XIN

《化学科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 167-171 doi: 10.1007/s11705-009-0006-y

摘要： The thermal degradation behaviors of polycarbonate/polymethylphenylsilsesquioxane (FRPC) composites were investigated by thermogravimetric analysis (TGA) under isothermal conditions in nitrogen atmosphere. The isothermal kinetics equation was used to describe the thermal degradation process. The results showed that activation energy ( ), in the case of isothermal degradation, was a quick increasing function of conversion (α) for polycarbonate (PC) but was a strong and decreasing function of conversion for FRPC. Under the isothermal condition, the addition of polymethylphenylsilsesquioxane (PMPSQ) retardanted the thermal degradation and enhanced the thermal stability of PC during the early and middle stages of thermal degradation. It also indicated a possible existence of a difference in nucleation, nuclei growth, and gas diffusion mechanism in the thermal degradation process between PC and FRPC. Meanwhile, the addition of PMPSQ influenced the lifetime of PC, but the composite still met the demand in manufacturing and application.

关键词： polycarbonate     polymethylphenylsilsesquioxane     thermal degradation kinetics     activation energy     lifetime    

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标题 作者 时间 类型 操作

我国草地的固碳功能

高树琴,赵霞,方精云

期刊论文

Using balance of seasonal herbage supply and demand to inform sustainable grassland management on the

Xinquan ZHAO, Liang ZHAO, Qi LI, Huai CHEN, Huakun ZHOU, Shixiao XU, Quanmin DONG, Gaolin WU, Yixin HE

期刊论文

INTENSIFICATION OF GRASSLAND-BASED DAIRY PRODUCTION AND ITS IMPACTS ON LAND, NITROGEN AND PHOSPHORUS

期刊论文

保障我国草地生态与食物安全的战略和政策

“中国草地生态保障与食物安全战略研究”项目组

期刊论文

GRASSLAND AGRICULTURE IN CHINA—A REVIEW

期刊论文

INTENSIFICATION OF GRASSLAND-BASED DAIRY PRODUCTION AND ITS IMPACTS ON LAND, NITROGEN AND PHOSPHORUS

Jouke OENEMA, Oene OENEMA

期刊论文

Allocation of grassland, livestock and arable based on the spatial and temporal analysis for food demand

Huilong LIN, Ruichao LI, Yifan LIU, Jingrong ZHANG, Jizhou REN

期刊论文

Influence of construction-induced damage on the degradation of freeze–thawed lightweight cellular concrete

期刊论文

Grassland management practices in Chinese steppes impact productivity, diversity and the relationship

Yingjun ZHANG, Wenjie LU, Hao ZHANG, Jiqiong ZHOU, Yue SHEN

期刊论文

Efficient degradation of orange II by ZnMn

Qingzhuo Ni, Hao Cheng, Jianfeng Ma, Yong Kong, Sridhar Komarneni

期刊论文

Promotive effect of pyridine on indole degradation by activated sludge under anoxic conditions

LI Yongmei, GU Guowei, LI Wenshu

期刊论文

anchored alginate/poly(acrylic acid/acrylamide) double-network hydrogel composites for efficient catalytic degradation

期刊论文

Sustainable wood-based nanotechnologies for photocatalytic degradation of organic contaminants in aquatic

期刊论文

藏北高原草地生态治理与畜牧业协同发展模式研究

干珠扎布,胡国铮,高清竹,江村旺扎,旦久罗布,参木友,巴桑旺堆,杨富裕,魏学红,杨永平

期刊论文

Thermal degradation kinetics and lifetime estimation for polycarbonate/polymethylphenylsilsesquioxane

Jiangbo WANG, Zhong XIN

期刊论文