Spatial, environmental, and material resources are important for tidal flats and wetlands, thus, a harmonious balance between utilization and protection should be maintained. In the present study, the concept of tidal...Spatial, environmental, and material resources are important for tidal flats and wetlands, thus, a harmonious balance between utilization and protection should be maintained. In the present study, the concept of tidal flat is defined, and its spatial limitation is also clarified. Located at the Yangtze Estuary, tidal flats in Shanghai area are selected for study. The relationship between water discharge and sediment transport of the Yangtze River, allowed exploration intensity and needs for wetland protection are discussed in the paper. The dynamic process and changing trend for different types of tidal flats are illustrated in detail. Regulations are proposed for a reasonable exploitation, dynamic protection, and ecosystem restoration of each individual tidal fiat and wetland. Some valuable suggestions are put forward for further study about the sustain＇able exploitation of offshore resources in Shanghai area.展开更多
The 2030 Agenda for Sustainable Development provides a core framework and platform for global development,mainly characterized by the incorporation of human rights protection responsibilities and explicit acknowledgme...The 2030 Agenda for Sustainable Development provides a core framework and platform for global development,mainly characterized by the incorporation of human rights protection responsibilities and explicit acknowledgment of the shared role of development and human rights in safeguarding human dignity and well-being.Human rights responsibilities require states to prioritize human development within their development agenda,achieve human rights through development,and adhere to human rights principles and standards.Integrating human rights responsibilities into the development agenda not only makes development more comprehensive but also provides legal constraints and monitoring mechanisms for the implementation of development goals.The 2030 Agenda for Sustainable Development redefines the relationship between development and human rights and is thus closely aligned with China’s practice of advancing sustainable development and human rights protection simultaneously.Guided by the people-centered development philosophy and new development philosophy,China has accomplished the historic tasks of the fight against poverty and the building of a moderately prosperous society in all respects,while significantly enhancing human rights protection.These achievements have provided a unique country-specific experience of“promoting human rights through development”for the implementation of sustainable development goals.展开更多
This paper investigated and analyzed the conservation and utilization of four local livestock breeds in Binzhou City:Wadi Sheep,Bohai Black Cattle,Wudi Donkey,and Lubei White Goat.Shortcomings in the protection and ut...This paper investigated and analyzed the conservation and utilization of four local livestock breeds in Binzhou City:Wadi Sheep,Bohai Black Cattle,Wudi Donkey,and Lubei White Goat.Shortcomings in the protection and utilization of local germplasm resources were pointed out,and strategies and recommendations were proposed to promote high-quality development of livestock and poultry genetic resources in Binzhou,including building a solid germplasm foundation,standardizing production,and driving innovation.This paper provides references for the conservation,development,and utilization of local genetic resources in Binzhou City.展开更多
Qaidam basin is an important part of National Key Development Area–Lanzhou-Xining Area,is a key region of resource development in Western Development,is a National Circular Economy Pilot Zone.The focus of
Firstly,the status quo of Pingxiang City as a resource-exhausted city was introduced firstly,and then the development situation of Anyuan Coal Mine,which is the representative of traditional coal industry in Pingxiang...Firstly,the status quo of Pingxiang City as a resource-exhausted city was introduced firstly,and then the development situation of Anyuan Coal Mine,which is the representative of traditional coal industry in Pingxiang,was summarized.Moreover,the classification and value of mining heritage were analyzed,and it is proposed that the development of mine heritage tourism and urban transformation should be combined.The planning of Anyuan National Mine Park under the background of urban transformation was analyzed to provides an idea for the protection and utilization of industrial heritage.展开更多
Through exploring and studying the rebuilding and protection planning of the Temple of YANG Shengan and Guihu Lake,the design principles and experience of rebuilding and protecting gardens of antiquity were summarized...Through exploring and studying the rebuilding and protection planning of the Temple of YANG Shengan and Guihu Lake,the design principles and experience of rebuilding and protecting gardens of antiquity were summarized,the effective approaches to integrate the rebuilding design and the protection of relics were explored and the suggestions for the protection and development of antiquity gardens were put forward.展开更多
Historic town was stressed as an important base of succeeding local cultures and characteristics,features and modes of protecting and developing historic towns in China were studied and summarized.By taking the Ancien...Historic town was stressed as an important base of succeeding local cultures and characteristics,features and modes of protecting and developing historic towns in China were studied and summarized.By taking the Ancient Daxu Town for an example,the protection of this ancient town was introduced,and deficiencies of its development were pointed out as:loss of "original" behaviors of the locals,commercial acts replacing "original" folk customs,incomplete tourist facilities,shabby traditional settlements and so on.In view of this,strategies for protecting and exploring the ancient town were proposed:properly making protection,construction and tourism planning,determining the direction of functional shift,realizing organic renovation of the old town,enhancing the planning and construction of tourist facilities,promoting the sustainable development of the ancient town;expanding the chain of tourism industry,strengthening regional integration;encouraging the locals to participate into the protection and development;applying the operation mode of "supervised by government,operated by enterprises,participated by locals".展开更多
The significance of protection and development of rural intangible cultural heritages was elaborated from the perspectives of rural harmonious culture,rural cultural innovation and rural cultural industry.Based on the...The significance of protection and development of rural intangible cultural heritages was elaborated from the perspectives of rural harmonious culture,rural cultural innovation and rural cultural industry.Based on these analyses,the present protection and development of rural intangible cultural heritages in Shaanxi was illustrated.In the end,all-dimensional countermeasures covering government,inheritors,NGO and the public were proposed for the effective protection and rational development of rural intangible cultural heritages in Shaanxi Province.展开更多
The recent progress on the proteins in edible insects was summarized, in- cluding the nutritional value, healthy value, food safety, extraction and content mea- surement of the proteins in edible insects, as well as t...The recent progress on the proteins in edible insects was summarized, in- cluding the nutritional value, healthy value, food safety, extraction and content mea- surement of the proteins in edible insects, as well as the main development direc- tion of edible insect proteins. And we also pointed out the bottlenecks that restricted the development and utilization of proteins in edible insects, and proposed the prospect of the research, development and utilization of edible insects proteins.展开更多
In the new era, marine resources are a powerful booster for a country's economic development. Reasonable development and protection of marine resources are of utmost importance. According to the actual situation o...In the new era, marine resources are a powerful booster for a country's economic development. Reasonable development and protection of marine resources are of utmost importance. According to the actual situation of our country, the current development of marine resources in our country has serious ecological environment damage and over-exploitation of resources, which threatens the harmonious, stable and sustainable development of the entire marine ecosystem. In this regard, based on marine protection, this paper explains the development of marine resources, and puts forward some feasible suggestions for the development and utilization of marine resources in China, in order to promote the coordinated development of marine resources development and marine environmental protection, and to do a little for the protection of marine resources in China.展开更多
Patterns of spatial development and protection form a basic category of geoscience,and redesigning them is a popular subject of research in regional sustainable development that is important for ecological civilizatio...Patterns of spatial development and protection form a basic category of geoscience,and redesigning them is a popular subject of research in regional sustainable development that is important for ecological civilization construction.The authors here report a case study of Wuhan city using the circuit theory model and minimum cumulative resistance(MCR)model to rebalance its spatial protection and development.The results show the following:(1)Using the density of the gross domestic product(GDP),density of population,rate of urbanization,and access to transportation as evaluation indicators,seven core areas of development in Wuhan were identified,accounting for 59%of the total number of streets,that exhibited a “circular-satellite”spatial structure.(2)According to the importance of ecosystem services,ecological sensitivity,land use type,and slope of the terrain,the resistance surface of spatial development in Wuhan had a stereoscopic spatial form of an“inverted pyramid,”with high surroundings and a low center.The area of low resistance accounted for 6.64%of the total area of Wuhan.(3)Based on coupling analysis using the MCR and spatial morphological characteristics of current,nine axes of spatial development with a total area of 427.27 km2 and eight key strategic points with a total area of 40.02 km2 were identified.Streets that were prioritized for development accounted for 9.63%of Wuhan's total area.(4)By combining the characterization of the development axis with the structure of the three-level core area,we extracted the structure of spatial development of "one heart,two wings,and three belts" in Wuhan.The research framework and empirical results can provide scientific guidance for the urban spatial layout,the development of regional linkages,and ecological environmental protection in China.展开更多
Bulk mineral resources of iron ores, copper ores, bauxite, lead ores, zinc ores and potassium salt play a pivotal role on the world＇s and China＇s economic development. This study analyzed and predicted their resourc...Bulk mineral resources of iron ores, copper ores, bauxite, lead ores, zinc ores and potassium salt play a pivotal role on the world＇s and China＇s economic development. This study analyzed and predicted their resources base and potential, development and utilization and their world＇s and China＇s supply and demand situation in the future 20 years. The supply and demand of these six bulk mineral products are generally balanced, with a slight surplus, which will guarantee the stability of the international mineral commodity market supply. The six mineral resources （especially iron ores and copper ores） are abundant and have a great potential, and their development and utilization scale will gradually increase. Till the end of 2014, the reserve- production ratio of iron, copper, bauxite, lead, zinc ores and potassium salt was 95 years, 42 years, 100 years, 17 years, 37 years and 170 years, respectively. Except lead ores, the other five types all have reserve-production ratio exceeding 20 years, indicative of a high resources guarantee degree. If the utilization of recycled metals is counted in, the supply of the world＇s six mineral products will exceed the demand in the future twenty years. In 2015-2035, the supply of iron ores, refined copper, primary aluminum, refined lead, zinc and potassium salt will exceed their demand by 0.4-0.7 billion tons （Gt）, 5.0-6.0 million tons （Mt）, 1.1-8.9 Mt, 1.0-2.0 Mt, 1.2-2.0 Mt and 4.8-5.6 Mt, respectively. It is predicted that there is no problem with the supply side of bulk mineral products such as iron ores, but local or structural shortage may occur because of geopolitics, monopoly control, resources nationalism and trade friction. Affected by China＇s compressed industrialized development model, the demand of iron ores （crude steel）, potassium salt, refined lead, refined copper, bauxite （primary aluminum） and zinc will gradually reach their peak in advance. The demand peak of iron ores （crude steel） will reach around 2015, 2016 for potassium salt, 2020 for refined lead, 2021 for bauxite （primary aluminum）, 2022 for refined copper and 2023 for zinc. China＇s demand for iron ores （crude steel）, bauxite （primary aluminum） and zinc in the future 20 years will decline among the world＇s demand, while that for refined copper, refined lead and potassium salt will slightly increase. The demand for bulk mineral products still remains high. In 2015-2035, China＇s accumulative demand for iron ores （crude steel） will be 20.313 Gt （13.429 Gt）, 0.304 Gt for refined copper, 2.466 Gt （0.616 Gt） of bauxite （primary aluminum）, 0.102 Gt of refined lead, 0.138 Gt of zinc and 0.157 Gt of potassium salt, and they account for the world＇s YOY （YOY） accumulative demand of 35.17%, 51.09%, 48.47%, 46.62%, 43.95% and 21.84%, respectively. This proportion is 49.40%, 102.52%, 87.44%, 105.65%, 93.62% and 106.49% of that in 2014, respectively. From the supply side of China＇s bulk mineral resources, it is forecasted that the accumulative supply of primary （mine） mineral products in 2015-2035 is 4.046 Gt of iron ores, 0.591 Gt of copper, 1.129 Gt of bauxite, 63.661 Mt of （mine） lead, 0.109 Gt of （mine） zinc and 0.128 Gt of potassium salt, which accounts for 8.82%, 13.92%, 26.67%, 47.09%, 33.04% and 15.56% of the world＇s predicted YOY production, respectively. With the rapid increase in the smelting capacity of iron and steel and alumina, the rate of capacity utilization for crude steel, refined copper, alumina, primary aluminum and refined lead in 2014 was 72.13%, 83.63%, 74.45%, 70.76% and 72.22%, respectively. During 2000-2014, the rate of capacity utilization for China＇s crude steel and refined copper showed a generally fluctuating decrease, which leads to an insufficient supply of primary mineral products. It is forecasted that the supply insufficiency of iron ores in 2015-2035 is 17.44 Gt, 0.245 Gt of copper in copper concentrates, 1.337 Gt of bauxite, 38.44 Mt of lead in lead concentrates and 29.19 Mt of zinc in zinc concentrates. China has gradually raised the utilization of recycled metals, which has mitigated the insufficient supply of primary metal products to some extent. It is forecasted that in 2015-2035 the accumulative utilization amount of steel scrap （iron ores） is 3.27 Gt （5.08 Gt）, 70.312 Mt of recycled copper, 0.2 Gt of recycled aluminum, 48 Mt of recycled lead and 7.7 Mt of recycled zinc. The analysis on the supply and demand situation of China＇s bulk mineral resources in 2015-2035 suggests that the supply-demand contradiction for these six types of mineral products will decrease, indicative of a generally declining external dependency. If the use of recycled metal amount is counted in, the external dependency of China＇s iron, copper, bauxite, lead, zinc and potassium salt will be 79%, 65%, 26%, 8%, 16% and 18% in 2014, respectively. It is predicted that this external dependency will decrease to 62%, 64%, 20%, -0.93%, 16% and 14% in 2020, respectively, showing an overall decreasing trend. We propose the following suggestions correspondingly. （1） The demand peak of China＇s crude steel and potassium salt will reach during 2015-2023 in succession. Mining transformation should be planned and deployed in advance to deal with the arrival of this demand peak. （2） The supply-demand contradiction of China＇s bulk mineral resources will mitigate in the future 20 years, and the external dependency will decrease accordingly. It is suggested to adjust the mineral resources management policies according to different minerals and regions, and regulate the exploration and development activities. （3） China should further establish and improve the forced mechanism of resolving the smelting overcapacity of steel, refined copper, primary aluminum, lead and zinc to really achieve the goal of ＂reducing excess production capacity＂. （4） In accordance with the national strategic deployment of ＂One Belt One Road＂, China should encourage the excess capacity of steel, copper, alumina and primary aluminum enterprises to transfer to those countries or areas with abundant resources, high energy matching degree and relatively excellent infrastructure. Based on the national conditions, mining condition and geopolitics of the resources countries, we will gradually build steel, copper, aluminum and lead-zinc smelting bases, and potash processing and production bases, which will promote the excess capacity to transfer to the overseas orderly. （5） It is proposed to strengthen the planning and management of renewable resources recycling and to construct industrial base of renewable metal recycling. （6） China should promote the comprehensive development and utilization of paragenetic and associated mineral species to further improve the comprehensive utilization of bulk mineral resources.展开更多
Improving the efficiency with which natural resources are utilized is an indispensable for achieving sustainable development and carbon neutrality. By analyzing the utilization efficiency of energy, water, and land, w...Improving the efficiency with which natural resources are utilized is an indispensable for achieving sustainable development and carbon neutrality. By analyzing the utilization efficiency of energy, water, and land, we established a comprehensive natural resource utilization efficiency index(NRUEI). We then calculated the 2016 index for 165 cities in China,and investigated what caused it to vary. We found three main results:(1) the NRUEI varied greatly across China and there were significant positive correlations between urban energy utilization efficiency(EUE), water utilization efficiency(WUE) and land utilization efficiency(LUE);(2) the NRUEI showed a significant positive correlation with a city’s population size,economy(Gross Domestic Product(GDP)), and the level of urban social development(GDP per capita);(3) cities in East China have the highest natural resource utilization efficiency,while cities in Northeast China have the lowest. These results indicate that China’s increasing urban development is associated with rising natural resource utilization efficiency and that the city’s endowment of natural resources is an important factor affecting that efficiency. Further, the results showed that the determinants of a city’s NRUEI differed in large and small cities. Lastly, our results suggest that improving EUE is key for improving NRUEI in urban China, and different efficiencies can be improved intertwined. A major takeaway of this study is that there is great potential for improving natural resource utilization efficiency in Chinese cities and we include city-specific suggestions for efficiency improvements.展开更多
Yunnan and Guizhou are two provinces in Southwest China where in recent years drought disasters have occurred due to natural and human factors. This paper reviewed literature and summarized the related achievements of...Yunnan and Guizhou are two provinces in Southwest China where in recent years drought disasters have occurred due to natural and human factors. This paper reviewed literature and summarized the related achievements of water resources utilization and protection in Yunnan and Guizhou provinces. rivers, and karst ground water in the two provinces, and also This included characters and utilization of precipitation, the various explanations of drought （climate and human factors） and strategies for coping with droughts. Our concluding remarks highlight three lines of future studies： inequalities and equitable use of water distribution, better evaluation systems, and raising awareness through conservation practices.展开更多
Based on the carrying capacity of the resources and the environment,this article defines the connotation of the land multifunctional space(LMFS)from three aspects,ecological protection,agricultural production and urba...Based on the carrying capacity of the resources and the environment,this article defines the connotation of the land multifunctional space(LMFS)from three aspects,ecological protection,agricultural production and urban construction,in the new era of land space planning system.Moreover,a framework is constructed for the coordinated development of the multi-functional oriented space to match the use of land space(ULS)with the supply of resources and environment(SRE).Based on this,the technology and methods of comprehensive evaluation,dominance recognition,and matching relationship division functions of the use of land space(FULS)and functions of the supply of resources and environment(FSRE)are discussed.The advantageous functions of the use of land space(AFULS)and advantageous functions of the supply of resources and environment(AFSRE)are also identified in the study area.A LMFS coordinated development system integrating“function position-comprehensive partition-regulation strategy”is proposed.Through the empirical study of Shandong province,we found that,first,the FULS of ecological protection space in the province is mainly found in high value areas,and the FSRE is mainly in low value areas,which has certain complementarity in the space.The FULS of agricultural production space is mainly observed in high value areas,the FSRE is mainly in middle value areas,and the spatial distribution is balanced and staggered.The FULS of the urban construction space and the FSRE are mainly in middle values areas,and the spatial distribution is basically similar.Second,the FULS in the study area is dominated by the single advantage of agricultural production and urban construction,while the FSRE has a relatively balanced distribution of the advantages of ecological protection,single agricultural production and compound advantages of agricultural production and urban construction,and urban construction and ecological protection.The matching between the two is mainly at high and middle levels.Specifically,70%of the province’s land space still has a certain development and utilization potential,and 30%of ULS intensity is close to or exceeds the resource and environment carrying capacity.Third,considering the comprehensive impact of resource endowment,social and economic development and policy and institutional environment on different matching relationships,this paper constructs the land spatial development strategic pattern of“two screens-seven regions-multicore”positioning and“four regions-eight categories”hierarchical area of Shandong at the macro level,and puts forward a differentiated land space development strategy.展开更多
This experiment was conducted to investigate the effect of dietary calcium(Ca)or phosphorus(P)deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age b...This experiment was conducted to investigate the effect of dietary calcium(Ca)or phosphorus(P)deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age based on our previous study,which indicated that dietary Ca or P deficiency impaired the bone development by regulating related Ca or P metabolic utilization parameters of broilers from 1 to 21 days of age.A total of 504 one-day-old Arbor Acres male broilers were randomly assigned to 1 of 4 treatments with 7 replicates in a completely randomized design,and fed the normal control and Ca-or P-deficient diets from 1 to 21 days of age.At 22 days of age,the broilers were further fed the normal control diet(0.90%Ca+0.35%non-phytate P(NPP)),the P-deficient diet(0.90%Ca+0.18%NPP),the Ca-deficient diet(0.30%Ca+0.35%NPP)or the Ca and P-deficient diet(0.30%Ca+0.18%NPP),respectively.The results showed that dietary Ca or P deficiency decreased(P<0.05)tibia bone mineral density(BMD),bone breaking strength(BBS),ash content,tibia ash Ca content and serum P content on days 28 and 42,but increased(P<0.05)tibia alkaline phosphatase(ALP)activity of broilers on day 42 compared with the control group.Furthermore,the broilers fed the P-deficient diet had the lowest(P<0.05)tibia BMD,BBS,ash content,serum P content and the highest(P<0.05)serum Ca content on day 28 compared with those fed the Ca-deficient or Ca and P-deficient diets.The results from the present study indicated that the bone development and related Ca or P metabolic utilization parameters of broilers were the most sensitive to dietary P deficiency,followed by dietary Ca deficiency or Ca and P-deficiency;dietary Ca or P deficiency impaired the bone development possibly by regulating serum Ca and P contents as well as tibia Ca content and ALP activity of broilers from 22 to 42 days of age.展开更多
Turpan Basin is a unique geographic region in China. The topography of the Basin is closed and the climate is extremely dry. The shortage of water resource has been restricting the existence and development of the oas...Turpan Basin is a unique geographic region in China. The topography of the Basin is closed and the climate is extremely dry. The shortage of water resource has been restricting the existence and development of the oasis in Turpan Basin. This paper briefly analyzes the characteristics of the basin's water resources, and expounds the processes of their utilization and regional development. It points out that the exploration of water resource is close to the limit and the utilization of water resource is unreasonable. So it is nonrealistic to follow the traditional exploration pattern. According to the transforming pattern between runoff and groundwater in the basin, an overall planning of the utilization of the water resource is advanced. Based on the relation between the maintenance of Aydingkol Lake and the existence of the oasis, the amount of water resource used must be controlled in order to guarantee the existence of the lake. The orientation of the utilization of water resource is to improve the management level of water resource, and to apply advanced water saving technology. Building up an economic system which can effectively use water resource is the orientation of the oasis sustainable economic development.展开更多
Huadianba in the Cangshan Mountain, a region where key ecosystem types and species under prior protection are concentrated, is the first choice for the comprehensive protection and development of biodiversity. In this...Huadianba in the Cangshan Mountain, a region where key ecosystem types and species under prior protection are concentrated, is the first choice for the comprehensive protection and development of biodiversity. In this study, natural conditions, location and current protection and development of Huadianba were introduced, major problems emerging in the protection and management were summarized, and pertinent measures were proposed as a reference for the scientific development and protection of Huadianba.展开更多
The existence of a large number of idle homesteads in rural areas not only causes waste of land resources,but also injures farmers' property rights and hinders the implementation of rural revitalization strategy. ...The existence of a large number of idle homesteads in rural areas not only causes waste of land resources,but also injures farmers' property rights and hinders the implementation of rural revitalization strategy. The emergence and vigorous development of rural leisure agriculture provides a new way of utilization and method for the development and utilization of rural homesteads. From the perspective of leisure agriculture,this paper analyzed the characteristics,advantages and disadvantages of the overall development model of rural idle homestead,farmstay model and characteristic industry development model,and discussed the actual case to enrich the research on the development and utilization of idle homestead. It pointed out that there are problems such as insufficient tourism resources and single management content,lack of legal basis for revitalizing the homestead,lagging reform of rural land property rights system,and difficulty in expanding the space for leisure tourism development in the process of developing rural idle homestead. It is recommended to provide reference for the effective improvement of the efficiency of idle homestead utilization,increase farmers' income,and promote the rural revitalization strategy.展开更多
Background:Replacement gilts are typically fed ad libitum,whereas emerging evidence from human and rodent studies has revealed that time-restricted access to food has health benefits.The objective of this study was to...Background:Replacement gilts are typically fed ad libitum,whereas emerging evidence from human and rodent studies has revealed that time-restricted access to food has health benefits.The objective of this study was to investigate the effect of meal frequency on the metabolic status and ovarian follicular development in gilts.Methods:A total of 36 gilts(Landrace×Yorkshire)with an age of 150±3 d and a body weight of 77.6±3.8 kg were randomly allocated into one of three groups(n=12 in each group),and based on the group allocation,the gilts were fed at a frequency of one meal(T1),two meals(T2),or six meals per day(T6)for 14 consecutive weeks.The effects of the meal frequency on growth preference,nutrient utilization,short-chain fatty acid production by gut microbial,the post-meal dynamics in the metabolic status,reproductive hormone secretions,and ovarian follicular development in the gilts were measured.Results:The gilts in the T1 group presented a higher average daily gain(+48 g/d,P<0.05)and a higher body weight(+4.9 kg,P<0.05)than those in the T6 group.The meal frequency had no effect on the apparent digestibility of dry matter,crude protein,ether extract,ash,and gross energy,with the exception that the T1 gilts exhibited a greater NDF digestibility than the T6 gilts(P<0.05).The nitrogen balance analysis revealed that the T1 gilts presented decreased urine excretion of nitrogen(−8.17 g/d,P<0.05)and higher nitrogen retention(+9.81 g/d,P<0.05),and thus exhibited higher nitrogen utilization than the T6 gilts.The time-course dynamics of glucose,α-amino nitrogen,urea,lactate,and insulin levels in serum revealed that the T1 group exhibited higher utilization of nutrients after a meal than the T2 or T6 gilts.The T1 gilts also had a higher acetate content and SCFAs in feces than the T6 gilts(P<0.05).The age,body weight and backfat thickness of the gilts at first estrous expression were not affected by the meal frequency,but the gilts in the T1 group had higher levels of serum luteinizing hormone on the 18th day of the 3rd estrus cycle and 17β-estradiol,a larger number of growing follicles and corpora lutea,and higher mRNA expression levels of genes related to follicular development on the 19th day of the 3rd estrus cycle.Conclusions:The current findings revealed the benefits of a lower meal frequency equal feed intake on nutrient utilization and reproductive function in replacement gilts,and thus provide new insights into the nutritional strategy for replacement gilts,and the dietary pattern for other mammals,such as humans.展开更多
文摘Spatial, environmental, and material resources are important for tidal flats and wetlands, thus, a harmonious balance between utilization and protection should be maintained. In the present study, the concept of tidal flat is defined, and its spatial limitation is also clarified. Located at the Yangtze Estuary, tidal flats in Shanghai area are selected for study. The relationship between water discharge and sediment transport of the Yangtze River, allowed exploration intensity and needs for wetland protection are discussed in the paper. The dynamic process and changing trend for different types of tidal flats are illustrated in detail. Regulations are proposed for a reasonable exploitation, dynamic protection, and ecosystem restoration of each individual tidal fiat and wetland. Some valuable suggestions are put forward for further study about the sustain＇able exploitation of offshore resources in Shanghai area.
文摘The 2030 Agenda for Sustainable Development provides a core framework and platform for global development,mainly characterized by the incorporation of human rights protection responsibilities and explicit acknowledgment of the shared role of development and human rights in safeguarding human dignity and well-being.Human rights responsibilities require states to prioritize human development within their development agenda,achieve human rights through development,and adhere to human rights principles and standards.Integrating human rights responsibilities into the development agenda not only makes development more comprehensive but also provides legal constraints and monitoring mechanisms for the implementation of development goals.The 2030 Agenda for Sustainable Development redefines the relationship between development and human rights and is thus closely aligned with China’s practice of advancing sustainable development and human rights protection simultaneously.Guided by the people-centered development philosophy and new development philosophy,China has accomplished the historic tasks of the fight against poverty and the building of a moderately prosperous society in all respects,while significantly enhancing human rights protection.These achievements have provided a unique country-specific experience of“promoting human rights through development”for the implementation of sustainable development goals.
基金Supported by Binzhou Social Sciences Planning Project in 2024(24-SKGH-051)Binzhou Comprehensive Experimental Station Project of Shandong Provincial Forage Industry Technology System(SDAIT-23-10).
文摘This paper investigated and analyzed the conservation and utilization of four local livestock breeds in Binzhou City:Wadi Sheep,Bohai Black Cattle,Wudi Donkey,and Lubei White Goat.Shortcomings in the protection and utilization of local germplasm resources were pointed out,and strategies and recommendations were proposed to promote high-quality development of livestock and poultry genetic resources in Binzhou,including building a solid germplasm foundation,standardizing production,and driving innovation.This paper provides references for the conservation,development,and utilization of local genetic resources in Binzhou City.
基金sponsored by China Academy of Engineering Major Consulting Project (No: 2012-ZD-14)
文摘Qaidam basin is an important part of National Key Development Area–Lanzhou-Xining Area,is a key region of resource development in Western Development,is a National Circular Economy Pilot Zone.The focus of
文摘Firstly,the status quo of Pingxiang City as a resource-exhausted city was introduced firstly,and then the development situation of Anyuan Coal Mine,which is the representative of traditional coal industry in Pingxiang,was summarized.Moreover,the classification and value of mining heritage were analyzed,and it is proposed that the development of mine heritage tourism and urban transformation should be combined.The planning of Anyuan National Mine Park under the background of urban transformation was analyzed to provides an idea for the protection and utilization of industrial heritage.
文摘Through exploring and studying the rebuilding and protection planning of the Temple of YANG Shengan and Guihu Lake,the design principles and experience of rebuilding and protecting gardens of antiquity were summarized,the effective approaches to integrate the rebuilding design and the protection of relics were explored and the suggestions for the protection and development of antiquity gardens were put forward.
基金Supported by Scientific Research Program of the Educational Department of Guangxi([2004]20)the Humanities and Social Sciences Research Foundation of the Ministry of Education (09YJA630150)~~
文摘Historic town was stressed as an important base of succeeding local cultures and characteristics,features and modes of protecting and developing historic towns in China were studied and summarized.By taking the Ancient Daxu Town for an example,the protection of this ancient town was introduced,and deficiencies of its development were pointed out as:loss of "original" behaviors of the locals,commercial acts replacing "original" folk customs,incomplete tourist facilities,shabby traditional settlements and so on.In view of this,strategies for protecting and exploring the ancient town were proposed:properly making protection,construction and tourism planning,determining the direction of functional shift,realizing organic renovation of the old town,enhancing the planning and construction of tourist facilities,promoting the sustainable development of the ancient town;expanding the chain of tourism industry,strengthening regional integration;encouraging the locals to participate into the protection and development;applying the operation mode of "supervised by government,operated by enterprises,participated by locals".
基金Supported by Research Program of Shaanxi Educational Department:Study on Protection of Intellectual Property in the Development of Shaanxi Creative Industries-With the Architectural Design Industry asa Case Study(11JK0198)~~
文摘The significance of protection and development of rural intangible cultural heritages was elaborated from the perspectives of rural harmonious culture,rural cultural innovation and rural cultural industry.Based on these analyses,the present protection and development of rural intangible cultural heritages in Shaanxi was illustrated.In the end,all-dimensional countermeasures covering government,inheritors,NGO and the public were proposed for the effective protection and rational development of rural intangible cultural heritages in Shaanxi Province.
基金Supported by the Special Fund for Agro-scientific Research in the Public Interest(200904025)the Natural Science Foundation of Beijing(6122024)+1 种基金the Surface Project of the Science and Technology Development Program of Beijing Municipal Education Commission(KM200900005002)the Project for the Agricultural Science and Technology of Beijing(20110115)~~
文摘The recent progress on the proteins in edible insects was summarized, in- cluding the nutritional value, healthy value, food safety, extraction and content mea- surement of the proteins in edible insects, as well as the main development direc- tion of edible insect proteins. And we also pointed out the bottlenecks that restricted the development and utilization of proteins in edible insects, and proposed the prospect of the research, development and utilization of edible insects proteins.
文摘In the new era, marine resources are a powerful booster for a country's economic development. Reasonable development and protection of marine resources are of utmost importance. According to the actual situation of our country, the current development of marine resources in our country has serious ecological environment damage and over-exploitation of resources, which threatens the harmonious, stable and sustainable development of the entire marine ecosystem. In this regard, based on marine protection, this paper explains the development of marine resources, and puts forward some feasible suggestions for the development and utilization of marine resources in China, in order to promote the coordinated development of marine resources development and marine environmental protection, and to do a little for the protection of marine resources in China.
基金National Natural Science Foundation of China,No.71974070,No.41501593Social Sciences Foundation of Ministry of Education of China,No.19YJCZH068Scientific Research Project of Hubei Provincial Natural Resources Department,No.ZRZY2019KY08。
文摘Patterns of spatial development and protection form a basic category of geoscience,and redesigning them is a popular subject of research in regional sustainable development that is important for ecological civilization construction.The authors here report a case study of Wuhan city using the circuit theory model and minimum cumulative resistance(MCR)model to rebalance its spatial protection and development.The results show the following:(1)Using the density of the gross domestic product(GDP),density of population,rate of urbanization,and access to transportation as evaluation indicators,seven core areas of development in Wuhan were identified,accounting for 59%of the total number of streets,that exhibited a “circular-satellite”spatial structure.(2)According to the importance of ecosystem services,ecological sensitivity,land use type,and slope of the terrain,the resistance surface of spatial development in Wuhan had a stereoscopic spatial form of an“inverted pyramid,”with high surroundings and a low center.The area of low resistance accounted for 6.64%of the total area of Wuhan.(3)Based on coupling analysis using the MCR and spatial morphological characteristics of current,nine axes of spatial development with a total area of 427.27 km2 and eight key strategic points with a total area of 40.02 km2 were identified.Streets that were prioritized for development accounted for 9.63%of Wuhan's total area.(4)By combining the characterization of the development axis with the structure of the three-level core area,we extracted the structure of spatial development of "one heart,two wings,and three belts" in Wuhan.The research framework and empirical results can provide scientific guidance for the urban spatial layout,the development of regional linkages,and ecological environmental protection in China.
基金supported by the China geological survey subproject of Dynamic Track and Evaluation of the Guarantee Degree of the Main Mineral Resources in China(No.121201103000150112,N1618-8)
文摘Bulk mineral resources of iron ores, copper ores, bauxite, lead ores, zinc ores and potassium salt play a pivotal role on the world＇s and China＇s economic development. This study analyzed and predicted their resources base and potential, development and utilization and their world＇s and China＇s supply and demand situation in the future 20 years. The supply and demand of these six bulk mineral products are generally balanced, with a slight surplus, which will guarantee the stability of the international mineral commodity market supply. The six mineral resources （especially iron ores and copper ores） are abundant and have a great potential, and their development and utilization scale will gradually increase. Till the end of 2014, the reserve- production ratio of iron, copper, bauxite, lead, zinc ores and potassium salt was 95 years, 42 years, 100 years, 17 years, 37 years and 170 years, respectively. Except lead ores, the other five types all have reserve-production ratio exceeding 20 years, indicative of a high resources guarantee degree. If the utilization of recycled metals is counted in, the supply of the world＇s six mineral products will exceed the demand in the future twenty years. In 2015-2035, the supply of iron ores, refined copper, primary aluminum, refined lead, zinc and potassium salt will exceed their demand by 0.4-0.7 billion tons （Gt）, 5.0-6.0 million tons （Mt）, 1.1-8.9 Mt, 1.0-2.0 Mt, 1.2-2.0 Mt and 4.8-5.6 Mt, respectively. It is predicted that there is no problem with the supply side of bulk mineral products such as iron ores, but local or structural shortage may occur because of geopolitics, monopoly control, resources nationalism and trade friction. Affected by China＇s compressed industrialized development model, the demand of iron ores （crude steel）, potassium salt, refined lead, refined copper, bauxite （primary aluminum） and zinc will gradually reach their peak in advance. The demand peak of iron ores （crude steel） will reach around 2015, 2016 for potassium salt, 2020 for refined lead, 2021 for bauxite （primary aluminum）, 2022 for refined copper and 2023 for zinc. China＇s demand for iron ores （crude steel）, bauxite （primary aluminum） and zinc in the future 20 years will decline among the world＇s demand, while that for refined copper, refined lead and potassium salt will slightly increase. The demand for bulk mineral products still remains high. In 2015-2035, China＇s accumulative demand for iron ores （crude steel） will be 20.313 Gt （13.429 Gt）, 0.304 Gt for refined copper, 2.466 Gt （0.616 Gt） of bauxite （primary aluminum）, 0.102 Gt of refined lead, 0.138 Gt of zinc and 0.157 Gt of potassium salt, and they account for the world＇s YOY （YOY） accumulative demand of 35.17%, 51.09%, 48.47%, 46.62%, 43.95% and 21.84%, respectively. This proportion is 49.40%, 102.52%, 87.44%, 105.65%, 93.62% and 106.49% of that in 2014, respectively. From the supply side of China＇s bulk mineral resources, it is forecasted that the accumulative supply of primary （mine） mineral products in 2015-2035 is 4.046 Gt of iron ores, 0.591 Gt of copper, 1.129 Gt of bauxite, 63.661 Mt of （mine） lead, 0.109 Gt of （mine） zinc and 0.128 Gt of potassium salt, which accounts for 8.82%, 13.92%, 26.67%, 47.09%, 33.04% and 15.56% of the world＇s predicted YOY production, respectively. With the rapid increase in the smelting capacity of iron and steel and alumina, the rate of capacity utilization for crude steel, refined copper, alumina, primary aluminum and refined lead in 2014 was 72.13%, 83.63%, 74.45%, 70.76% and 72.22%, respectively. During 2000-2014, the rate of capacity utilization for China＇s crude steel and refined copper showed a generally fluctuating decrease, which leads to an insufficient supply of primary mineral products. It is forecasted that the supply insufficiency of iron ores in 2015-2035 is 17.44 Gt, 0.245 Gt of copper in copper concentrates, 1.337 Gt of bauxite, 38.44 Mt of lead in lead concentrates and 29.19 Mt of zinc in zinc concentrates. China has gradually raised the utilization of recycled metals, which has mitigated the insufficient supply of primary metal products to some extent. It is forecasted that in 2015-2035 the accumulative utilization amount of steel scrap （iron ores） is 3.27 Gt （5.08 Gt）, 70.312 Mt of recycled copper, 0.2 Gt of recycled aluminum, 48 Mt of recycled lead and 7.7 Mt of recycled zinc. The analysis on the supply and demand situation of China＇s bulk mineral resources in 2015-2035 suggests that the supply-demand contradiction for these six types of mineral products will decrease, indicative of a generally declining external dependency. If the use of recycled metal amount is counted in, the external dependency of China＇s iron, copper, bauxite, lead, zinc and potassium salt will be 79%, 65%, 26%, 8%, 16% and 18% in 2014, respectively. It is predicted that this external dependency will decrease to 62%, 64%, 20%, -0.93%, 16% and 14% in 2020, respectively, showing an overall decreasing trend. We propose the following suggestions correspondingly. （1） The demand peak of China＇s crude steel and potassium salt will reach during 2015-2023 in succession. Mining transformation should be planned and deployed in advance to deal with the arrival of this demand peak. （2） The supply-demand contradiction of China＇s bulk mineral resources will mitigate in the future 20 years, and the external dependency will decrease accordingly. It is suggested to adjust the mineral resources management policies according to different minerals and regions, and regulate the exploration and development activities. （3） China should further establish and improve the forced mechanism of resolving the smelting overcapacity of steel, refined copper, primary aluminum, lead and zinc to really achieve the goal of ＂reducing excess production capacity＂. （4） In accordance with the national strategic deployment of ＂One Belt One Road＂, China should encourage the excess capacity of steel, copper, alumina and primary aluminum enterprises to transfer to those countries or areas with abundant resources, high energy matching degree and relatively excellent infrastructure. Based on the national conditions, mining condition and geopolitics of the resources countries, we will gradually build steel, copper, aluminum and lead-zinc smelting bases, and potash processing and production bases, which will promote the excess capacity to transfer to the overseas orderly. （5） It is proposed to strengthen the planning and management of renewable resources recycling and to construct industrial base of renewable metal recycling. （6） China should promote the comprehensive development and utilization of paragenetic and associated mineral species to further improve the comprehensive utilization of bulk mineral resources.
基金supported by the National Natural Science Foundation of China (Nos. 42101290 and 71533005)the Special Project on National Science and Technology Basic Resources Investigation of China (No. 2021FY100703)。
文摘Improving the efficiency with which natural resources are utilized is an indispensable for achieving sustainable development and carbon neutrality. By analyzing the utilization efficiency of energy, water, and land, we established a comprehensive natural resource utilization efficiency index(NRUEI). We then calculated the 2016 index for 165 cities in China,and investigated what caused it to vary. We found three main results:(1) the NRUEI varied greatly across China and there were significant positive correlations between urban energy utilization efficiency(EUE), water utilization efficiency(WUE) and land utilization efficiency(LUE);(2) the NRUEI showed a significant positive correlation with a city’s population size,economy(Gross Domestic Product(GDP)), and the level of urban social development(GDP per capita);(3) cities in East China have the highest natural resource utilization efficiency,while cities in Northeast China have the lowest. These results indicate that China’s increasing urban development is associated with rising natural resource utilization efficiency and that the city’s endowment of natural resources is an important factor affecting that efficiency. Further, the results showed that the determinants of a city’s NRUEI differed in large and small cities. Lastly, our results suggest that improving EUE is key for improving NRUEI in urban China, and different efficiencies can be improved intertwined. A major takeaway of this study is that there is great potential for improving natural resource utilization efficiency in Chinese cities and we include city-specific suggestions for efficiency improvements.
基金funded by the National Social Science Foundation of China (No. 10CGL050)
文摘Yunnan and Guizhou are two provinces in Southwest China where in recent years drought disasters have occurred due to natural and human factors. This paper reviewed literature and summarized the related achievements of water resources utilization and protection in Yunnan and Guizhou provinces. rivers, and karst ground water in the two provinces, and also This included characters and utilization of precipitation, the various explanations of drought （climate and human factors） and strategies for coping with droughts. Our concluding remarks highlight three lines of future studies： inequalities and equitable use of water distribution, better evaluation systems, and raising awareness through conservation practices.
基金National Natural Science Foundation of China,No.42077434,No.41771560Shandong Provincial Institutions of Higher Learning“Youth Innovation Team Development Plan”Project,No.2019RWG016。
文摘Based on the carrying capacity of the resources and the environment,this article defines the connotation of the land multifunctional space(LMFS)from three aspects,ecological protection,agricultural production and urban construction,in the new era of land space planning system.Moreover,a framework is constructed for the coordinated development of the multi-functional oriented space to match the use of land space(ULS)with the supply of resources and environment(SRE).Based on this,the technology and methods of comprehensive evaluation,dominance recognition,and matching relationship division functions of the use of land space(FULS)and functions of the supply of resources and environment(FSRE)are discussed.The advantageous functions of the use of land space(AFULS)and advantageous functions of the supply of resources and environment(AFSRE)are also identified in the study area.A LMFS coordinated development system integrating“function position-comprehensive partition-regulation strategy”is proposed.Through the empirical study of Shandong province,we found that,first,the FULS of ecological protection space in the province is mainly found in high value areas,and the FSRE is mainly in low value areas,which has certain complementarity in the space.The FULS of agricultural production space is mainly observed in high value areas,the FSRE is mainly in middle value areas,and the spatial distribution is balanced and staggered.The FULS of the urban construction space and the FSRE are mainly in middle values areas,and the spatial distribution is basically similar.Second,the FULS in the study area is dominated by the single advantage of agricultural production and urban construction,while the FSRE has a relatively balanced distribution of the advantages of ecological protection,single agricultural production and compound advantages of agricultural production and urban construction,and urban construction and ecological protection.The matching between the two is mainly at high and middle levels.Specifically,70%of the province’s land space still has a certain development and utilization potential,and 30%of ULS intensity is close to or exceeds the resource and environment carrying capacity.Third,considering the comprehensive impact of resource endowment,social and economic development and policy and institutional environment on different matching relationships,this paper constructs the land spatial development strategic pattern of“two screens-seven regions-multicore”positioning and“four regions-eight categories”hierarchical area of Shandong at the macro level,and puts forward a differentiated land space development strategy.
基金The present study was financially supported by the National Key R&D Program of China(2017YF0502200)the Key Program of the National Natural Science Foundation of China(31630073)+2 种基金the earmarked fund for China Agriculture Research System(CARS-41)the Agricultural Science and Technology Innovation Program,China(ASTIP-IAS09)the earmarked fund for Hebei Chicken Innovation Team of Modern Agro-Industry Technology Research System,China(HBCT2018150203 and HBCT2018150206).
文摘This experiment was conducted to investigate the effect of dietary calcium(Ca)or phosphorus(P)deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age based on our previous study,which indicated that dietary Ca or P deficiency impaired the bone development by regulating related Ca or P metabolic utilization parameters of broilers from 1 to 21 days of age.A total of 504 one-day-old Arbor Acres male broilers were randomly assigned to 1 of 4 treatments with 7 replicates in a completely randomized design,and fed the normal control and Ca-or P-deficient diets from 1 to 21 days of age.At 22 days of age,the broilers were further fed the normal control diet(0.90%Ca+0.35%non-phytate P(NPP)),the P-deficient diet(0.90%Ca+0.18%NPP),the Ca-deficient diet(0.30%Ca+0.35%NPP)or the Ca and P-deficient diet(0.30%Ca+0.18%NPP),respectively.The results showed that dietary Ca or P deficiency decreased(P<0.05)tibia bone mineral density(BMD),bone breaking strength(BBS),ash content,tibia ash Ca content and serum P content on days 28 and 42,but increased(P<0.05)tibia alkaline phosphatase(ALP)activity of broilers on day 42 compared with the control group.Furthermore,the broilers fed the P-deficient diet had the lowest(P<0.05)tibia BMD,BBS,ash content,serum P content and the highest(P<0.05)serum Ca content on day 28 compared with those fed the Ca-deficient or Ca and P-deficient diets.The results from the present study indicated that the bone development and related Ca or P metabolic utilization parameters of broilers were the most sensitive to dietary P deficiency,followed by dietary Ca deficiency or Ca and P-deficiency;dietary Ca or P deficiency impaired the bone development possibly by regulating serum Ca and P contents as well as tibia Ca content and ALP activity of broilers from 22 to 42 days of age.
文摘Turpan Basin is a unique geographic region in China. The topography of the Basin is closed and the climate is extremely dry. The shortage of water resource has been restricting the existence and development of the oasis in Turpan Basin. This paper briefly analyzes the characteristics of the basin's water resources, and expounds the processes of their utilization and regional development. It points out that the exploration of water resource is close to the limit and the utilization of water resource is unreasonable. So it is nonrealistic to follow the traditional exploration pattern. According to the transforming pattern between runoff and groundwater in the basin, an overall planning of the utilization of the water resource is advanced. Based on the relation between the maintenance of Aydingkol Lake and the existence of the oasis, the amount of water resource used must be controlled in order to guarantee the existence of the lake. The orientation of the utilization of water resource is to improve the management level of water resource, and to apply advanced water saving technology. Building up an economic system which can effectively use water resource is the orientation of the oasis sustainable economic development.
文摘Huadianba in the Cangshan Mountain, a region where key ecosystem types and species under prior protection are concentrated, is the first choice for the comprehensive protection and development of biodiversity. In this study, natural conditions, location and current protection and development of Huadianba were introduced, major problems emerging in the protection and management were summarized, and pertinent measures were proposed as a reference for the scientific development and protection of Huadianba.
基金Supported by Social Science Planning Project of Jiangxi Province(13GL42)Soft Science Project of Jiangxi Provincial Science and Technology Department(20141BBA10070&20141BBA10069)+2 种基金Science and Technology Research Project of Jiangxi Provincial Department of Education(GJJ14257)Project of Humanities and Social Science Foundation of Jiangxi Provincial Department of Education"The Guiding Mechanism and Policy Choice of Capital Management of Rural Land Management Rights in Jiangxi from the Perspective of Regional Differences"the Postgraduate Innovation Fund Project of Jiangxi Normal University in 2018"Evaluation and Policy Choice of Exit Mode of Right to Use Jiangxi Homestead under the Protection of Farmers'Rights and Interests"(YC2018-S174)
文摘The existence of a large number of idle homesteads in rural areas not only causes waste of land resources,but also injures farmers' property rights and hinders the implementation of rural revitalization strategy. The emergence and vigorous development of rural leisure agriculture provides a new way of utilization and method for the development and utilization of rural homesteads. From the perspective of leisure agriculture,this paper analyzed the characteristics,advantages and disadvantages of the overall development model of rural idle homestead,farmstay model and characteristic industry development model,and discussed the actual case to enrich the research on the development and utilization of idle homestead. It pointed out that there are problems such as insufficient tourism resources and single management content,lack of legal basis for revitalizing the homestead,lagging reform of rural land property rights system,and difficulty in expanding the space for leisure tourism development in the process of developing rural idle homestead. It is recommended to provide reference for the effective improvement of the efficiency of idle homestead utilization,increase farmers' income,and promote the rural revitalization strategy.
基金This study was supported by National Key R&D Program of China(2018YFD0501005)National Natural Science Foundation of China,PR China(31772616).
文摘Background:Replacement gilts are typically fed ad libitum,whereas emerging evidence from human and rodent studies has revealed that time-restricted access to food has health benefits.The objective of this study was to investigate the effect of meal frequency on the metabolic status and ovarian follicular development in gilts.Methods:A total of 36 gilts(Landrace×Yorkshire)with an age of 150±3 d and a body weight of 77.6±3.8 kg were randomly allocated into one of three groups(n=12 in each group),and based on the group allocation,the gilts were fed at a frequency of one meal(T1),two meals(T2),or six meals per day(T6)for 14 consecutive weeks.The effects of the meal frequency on growth preference,nutrient utilization,short-chain fatty acid production by gut microbial,the post-meal dynamics in the metabolic status,reproductive hormone secretions,and ovarian follicular development in the gilts were measured.Results:The gilts in the T1 group presented a higher average daily gain(+48 g/d,P<0.05)and a higher body weight(+4.9 kg,P<0.05)than those in the T6 group.The meal frequency had no effect on the apparent digestibility of dry matter,crude protein,ether extract,ash,and gross energy,with the exception that the T1 gilts exhibited a greater NDF digestibility than the T6 gilts(P<0.05).The nitrogen balance analysis revealed that the T1 gilts presented decreased urine excretion of nitrogen(−8.17 g/d,P<0.05)and higher nitrogen retention(+9.81 g/d,P<0.05),and thus exhibited higher nitrogen utilization than the T6 gilts.The time-course dynamics of glucose,α-amino nitrogen,urea,lactate,and insulin levels in serum revealed that the T1 group exhibited higher utilization of nutrients after a meal than the T2 or T6 gilts.The T1 gilts also had a higher acetate content and SCFAs in feces than the T6 gilts(P<0.05).The age,body weight and backfat thickness of the gilts at first estrous expression were not affected by the meal frequency,but the gilts in the T1 group had higher levels of serum luteinizing hormone on the 18th day of the 3rd estrus cycle and 17β-estradiol,a larger number of growing follicles and corpora lutea,and higher mRNA expression levels of genes related to follicular development on the 19th day of the 3rd estrus cycle.Conclusions:The current findings revealed the benefits of a lower meal frequency equal feed intake on nutrient utilization and reproductive function in replacement gilts,and thus provide new insights into the nutritional strategy for replacement gilts,and the dietary pattern for other mammals,such as humans.
