On the basis of 'The Statistical Data of Guangdong Province in 1981' and the 14 selected original variables, 107 counties and suburbs in Guangdong are classified. In the classification, cluster analysis is app...On the basis of 'The Statistical Data of Guangdong Province in 1981' and the 14 selected original variables, 107 counties and suburbs in Guangdong are classified. In the classification, cluster analysis is applied, and the cluster hierarchy of the agro-ecosystem is achieved with a computer. According to output level, planting structure, and input level of energy, there is an evident regionalism in the agro-ecosystem of Guangdong, which presents approximately concentric circles centralized by Guangzhou City.展开更多
Using the emergy analysis method,we conduct trend analysis of changes in the total emergy,input and output structure,various emergy indicators of agro-ecosystem in Hunan Province during the period 1999-2008.The result...Using the emergy analysis method,we conduct trend analysis of changes in the total emergy,input and output structure,various emergy indicators of agro-ecosystem in Hunan Province during the period 1999-2008.The results show that during the study period,total emergy input basically remained stable,but the emergy input structure was constantly optimized,of which the input of non-renewable industrial assistant emergy increased by 38.4%,from 4.00E +22 sej to 5.53E +22 sej,and the input of renewable organic emergy declined from 1.32E +23 sej to 1.20E + 23 sej;total emergy yield and yield efficiency of this system were promoted dramatically,and in 2008,the total emergy yield reached 1.69E +23 sej,increasing by 23.8% as against that in 1999,the net emergy yield ratio rose from 0.79 to 0.96;since the environmental loading ratio also tended to rise constantly,from 1.12 to 1.79,the sustainability index of this system also experienced the slow downward trend,from 0.71 to 0.54,always less than 1,indicating that the agriculture in Hunan Province is the high consumption-driven ecosystem in general,with obvious features of extensive development.展开更多
Alternative Land Use Services (ALUS) is an incentive-based program established in Canada to pay farmers for their voluntary delivery of ecosystem services (ES). All seven ALUS programs across the country were examined...Alternative Land Use Services (ALUS) is an incentive-based program established in Canada to pay farmers for their voluntary delivery of ecosystem services (ES). All seven ALUS programs across the country were examined using a standardized case-study approach based on site visits, reading internal documents, attending program meetings, and engaging in semi-structured interviews with program administrators, participating farmers, and advisory board members. Direct content analysis was used to highlight recurrent themes and emerging lessons in relation to the salient particulars of program physical location, administration framework, delivery of ES, and development and receipt by communities. Our three major findings are: 1) Overall, ALUS has been judged by participants to be a very successful program, whose strength is that it is completely voluntary, non-permanent, and readily adaptable to each location’s environmental conditions, economic funding base, and cultural milieu. 2) One serious shortcoming of all ALUS programs is a general lack of quantifiable data on their ability to increase ES. Instead, environmental benefits are either assumed or based on the idea that the areal extent of enrolled land is the sole measure of its environmental worth. 3) It may be that the social impact of ALUS is its greatest success. In this regard, for farmers, it is the process of engaging in land-use decision making and the recognition of their role as environmental stewards that is a bigger motivation for participating in an ALUS program than the modest financial incentives which they receive.展开更多
A research project on interaction between agroecosystems and global change has been accepted as a Category Ⅰ contribution to IGBP-GCTE (International Geosphere-Biosphere Programme-Global Change & Terrestrial Ecos...A research project on interaction between agroecosystems and global change has been accepted as a Category Ⅰ contribution to IGBP-GCTE (International Geosphere-Biosphere Programme-Global Change & Terrestrial Ecosystems) Core Research, the highest-level support GCTE has offered to an individual research project so far. This was confirmed by Prof. Noble, GCTE Chairman, in a letter to Prof. Peng Shaolin, Principal Investigator of展开更多
To accurately evaluate the carbon sequestration potential and better elucidate the relationship between the carbon cycle and regional climate change, using eddy covariance system, we conducted a long-term measurement ...To accurately evaluate the carbon sequestration potential and better elucidate the relationship between the carbon cycle and regional climate change, using eddy covariance system, we conducted a long-term measurement of CO 2 fluxes in the rain-fed winter wheat field of the Chinese Loess Plateau. The results showed that the annual net ecosystem CO 2 exchange (NEE) was (-71.6±5.7) and (-65.3±5.3) g C m-2 y-1 for 2008-2009 and 2009-2010 crop years, respectively, suggesting that the agro-ecosystem was a carbon sink (117.4-126.2 g C m-2 yr-1). However, after considering the harvested grain, the agro- ecosystem turned into a moderate carbon source. The variations in NEE and ecosystem respiration (R eco ) were sensitive to changes in soil water content (SWC). When SWC ranged form 0.15 to 0.21 m3 m-3, we found a highly significant relationship between NEE and photosynthetically active radiation (PAR), and a highly significant relationship between R eco and soil temperature (T s ). However, the highly significant relationships were not observed when SWC was outside the range of 0.15-0.21 m3 m-3. Further, in spring, the R eco instantly responded to a rapid increase in SWC after effective rainfall events, which could induce 2 to 4-fold increase in daily R eco , whereas the R eco was also inhibited by heavy summer rainfall when soils were saturated. Accumulated R eco in summer fallow period decreased carbon fixed in growing season by 16- 25%, indicating that the period imposed negative impacts on annual carbon sequestration.展开更多
Nitrification and denitrification are two key links of nitrogen flow cycle in soil.N2O and N2,generated from biochemical process of nitrogen,can cause not only the nitrogen losses and reduction of nitrogen use efficie...Nitrification and denitrification are two key links of nitrogen flow cycle in soil.N2O and N2,generated from biochemical process of nitrogen,can cause not only the nitrogen losses and reduction of nitrogen use efficiency,but also the boosted concentration of greenhouse gases,severely endangering the environment.Accordingly,nitrification-denitrification has been more and more concerned from whether an agricultural view,or an environmental one.Referring to the related literatures published at home and abroad in recent years,we overviewed the denitrification-caused N loss and N2O emission in various agro-ecosystems,and based on which we put forward countermeasures to reduce the denitrification-caused N loss and N2O emission and its research prospects in the future.展开更多
Topsoil soil organic carbon(SOC) data were collected from long-term Chinese agro-ecosystem experiments presented in 76 reports with measurements over 1977 and 2006.The data set comprised 481 observations(135 rice padd...Topsoil soil organic carbon(SOC) data were collected from long-term Chinese agro-ecosystem experiments presented in 76 reports with measurements over 1977 and 2006.The data set comprised 481 observations(135 rice paddies and 346 dry croplands) of SOC under different fertilization schemes at 70 experimental sites(28 rice paddies and 42 dry croplands).The data set covered 16 dominant soil types found in croplands across 23 provinces of China's Mainland.The fertilization schemes were grouped into six categories:N(inorganic nitrogen fertilizer only),NP(compound inorganic nitrogen and phosphorus fertilizers),NPK(compound inorganic nitrogen,phosphorus and potassium fertilizers),O(organic fertilizers only),OF(combined inorganic/organic fertilization) and Others(other unbalanced fertilizations such as P only,K only,P plus K and N plus K).Relative change in SOC content was analyzed,and rice paddies and dry croplands soils were compared.There was an overall temporal increase in topsoil SOC content,and relative annual change(RAC,g kg-1 yr-1) ranged -0.14-0.60(0.13 on average) for dry cropland soils and -0.12-0.70(0.19 on average) for rice paddies.SOC content increase was higher in rice paddies than in dry croplands.SOC increased across experimental sites,but was higher under organic fertilization and combined organic/inorganic fertilizations than chemical fertilizations.SOC increase was higher under balanced chemical fertilizations with compound N,P and K fertilizers than unbalanced fertilizations such as N only,N plus P,and N plus K.The effects of specific rational fertilizations on SOC increase persisted for 15 years in dry croplands and 20 years in rice paddies,although RAC values decreased generally as the experiment duration increased.Therefore,the extension of rational fertilization in China's croplands may offer a technical option to enhance C sequestration potential and to sustain long-term crop productivity.展开更多
Agriculture under changing climate scenario is facing major challenges of water scarcity and resource imbalances.Crop water productivity(WP)may act as an indicator of crop responses to water limitation.Organic amendme...Agriculture under changing climate scenario is facing major challenges of water scarcity and resource imbalances.Crop water productivity(WP)may act as an indicator of crop responses to water limitation.Organic amendments such as biochar and manure application to soil are suggested for improving soil quality and reducing water requirements from agricultural sector.However,studies exploring the impact of biochar as sole or in combination with organic and/or chemical fertilizers on WP in dry tropical agro-ecosystems are limited.In this study,we observed the effect of rice-husk ash(RHA,biochar)along with farm-yard manure(FYM)and chemical fertilizers(CF)under varying water conditions on soil hydro-physical properties,yield and WP of wheat crop.Water-filled pore space(WFPS),grain and straw yield,irrigation and total water productivity varied significantly(at P<0.001)at treatment level.Grain and straw yield were found higher under sole and combined CF applied treatments.Sole and combined RHA and FYM amendment improved water holding capacity(WHC)and WFPS,whereas a decrease in crop yield was observed as compared to the control.Irrigation and total water productivity were found higher under combined RHA+FYM and sole CF treatments with reduced water supply(except sole CF)as compared to control and sole RHA treatments with full water irrigation.Crop water productivity was found positively correlated with grain and straw yields,however,significant correlations were not observed with WHC and WFPS.Results indicate that increasing soil hydro-physical properties in silty-loam soil may hinder crop yield and WP under sole biochar applied soils.Overall,the implications of the study would help in devising agro-management practices based on combined application of RHA and FYM with reduced chemical fertilizer and water inputs to mitigate the impacts of climate change without compromising crop yield in the highly vulnerable dry tropical agro-ecosystem of India.Moreover,long-term studies are needed in these ecosystems to identify the appropriate agricultural package for mitigating the forthcoming water scarcity conditions.展开更多
Research on carbon cycling has attracted attention from both scientists and policy-makers.Based on material flow analysis,this study systematically budgets the carbon inputs,outputs and balance from 1980 to 2013 for C...Research on carbon cycling has attracted attention from both scientists and policy-makers.Based on material flow analysis,this study systematically budgets the carbon inputs,outputs and balance from 1980 to 2013 for China's agro-ecosystem and its sub-systems,including agricultural land use,livestock breeding and rural life. The results show that from1980 to 2013,both the carbon input and output were growing gradually,with the carbon input doubling from 1.6 Pg C/year in 1980 to 3.4 Pg C/year in 2013,while carbon output grew from 2.2 Pg C/year in 1980 to 3.8 Pg C/year in 2013. From 1980 to 2013,the crop production system in China has remained a carbon source,and the agricultural land uses were also almost all carbon sources instead of carbon sinks. As soil carbon stock plays a very important role in deciding the function of China's agro-ecosystem as a carbon sink or source,practices that can promote carbon storage and sequestration will be an essential component of low carbon agriculture development in China.展开更多
农业生态学作为生态学和农业科学的交叉学科,有助于优化传统农业体系和生态农业实践。为厘清国际农业生态学的发展现状和研究趋势,本文借助CiteSpace对2012—2021年Web of Science核心数据库的国际农业生态学论文进行计量分析,研究发现...农业生态学作为生态学和农业科学的交叉学科,有助于优化传统农业体系和生态农业实践。为厘清国际农业生态学的发展现状和研究趋势,本文借助CiteSpace对2012—2021年Web of Science核心数据库的国际农业生态学论文进行计量分析,研究发现:1)国际农业生态学的热点议题主要是农业生态系统的整体表现及其评价的研究、以生态农业实践为基础的科学研究以及关于生态农业社会运动与社会影响的研究等。2)国际农业生态研究人员在农业生态学领域有很多基础性和创新性研究,主要围绕农业生态转型与生态农业产业形态、生态农业社会运动以及如何调节农业生态系统内部诸生态因子、建构可持续农业生态体系展开。3)国际农业生态学研究的前沿趋势不仅聚焦于涉及自然学科的生物多样性保护、景观生态安全格局、农业种植体系与农业环境污染等内容,还涉及社会管理相关领域的知识型农民培育、农业教育和参与式治理模式等方面。未来国内农业生态学的发展可在立足国情的基础上,加强国际交流合作,同时,紧随国家发展战略,推动新型农业技术的创新发展。展开更多
中国北方农牧交错带是我国重要的生态安全屏障之一,面临经济发展与脆弱生态环境保护间的突出矛盾。生态系统服务的定量研究是生态可持续管理的重要科学依据,也是当前的研究热点之一。以北方农牧交错带的核心区域--内蒙古中西部地区为例...中国北方农牧交错带是我国重要的生态安全屏障之一,面临经济发展与脆弱生态环境保护间的突出矛盾。生态系统服务的定量研究是生态可持续管理的重要科学依据,也是当前的研究热点之一。以北方农牧交错带的核心区域--内蒙古中西部地区为例,结合中高分辨率遥感数据和生物物理模型准确量化了2000-2018年关键生态系统服务,基于Getis-Ord G*方法分析了生态系统服务的空间格局,考虑地理数据的空间自相关性选取了空间回归模型探索其影响因子。结果表明:(1)净初级生产力(NPP,Net primary productivity)、土壤水蚀控制服务(SC,Soil conservation)、产水量(WY,Water yield)及三层土壤含水量(SM1,Soil moisture of top layer;SM2,Soil moisture of middle layer;SM3,Soil moisture of bottom layer)在东部较高,防风固沙服务(SF,Sand fixation)在南部和西部较高;(2)以上生态系统服务受气候变化、景观格局、地形和土壤条件等综合影响,不同影响因素对生态系统服务的作用存在差异。NPP受森林景观格局和归一化植被指数的影响最为显著;WY、SM1、SM2、SM3及SC受降水量的影响较为显著;风速和表层土壤砂粒含量对SF影响最为显著。研究结果可以为优化景观格局和土地系统,缓解中国北方农牧交错带的社会-生态矛盾提供科学依据和案例参考。展开更多
文摘On the basis of 'The Statistical Data of Guangdong Province in 1981' and the 14 selected original variables, 107 counties and suburbs in Guangdong are classified. In the classification, cluster analysis is applied, and the cluster hierarchy of the agro-ecosystem is achieved with a computer. According to output level, planting structure, and input level of energy, there is an evident regionalism in the agro-ecosystem of Guangdong, which presents approximately concentric circles centralized by Guangzhou City.
基金Supported by National Social Science Foundation (11BJY029)Hunan Social Science Fund Project (2010YBB348)+1 种基金Open Fund for Hunan University Innovation Platform (10K080)Key Project of Soft Science in Hunan Province (2011ZK2046)
文摘Using the emergy analysis method,we conduct trend analysis of changes in the total emergy,input and output structure,various emergy indicators of agro-ecosystem in Hunan Province during the period 1999-2008.The results show that during the study period,total emergy input basically remained stable,but the emergy input structure was constantly optimized,of which the input of non-renewable industrial assistant emergy increased by 38.4%,from 4.00E +22 sej to 5.53E +22 sej,and the input of renewable organic emergy declined from 1.32E +23 sej to 1.20E + 23 sej;total emergy yield and yield efficiency of this system were promoted dramatically,and in 2008,the total emergy yield reached 1.69E +23 sej,increasing by 23.8% as against that in 1999,the net emergy yield ratio rose from 0.79 to 0.96;since the environmental loading ratio also tended to rise constantly,from 1.12 to 1.79,the sustainability index of this system also experienced the slow downward trend,from 0.71 to 0.54,always less than 1,indicating that the agriculture in Hunan Province is the high consumption-driven ecosystem in general,with obvious features of extensive development.
文摘Alternative Land Use Services (ALUS) is an incentive-based program established in Canada to pay farmers for their voluntary delivery of ecosystem services (ES). All seven ALUS programs across the country were examined using a standardized case-study approach based on site visits, reading internal documents, attending program meetings, and engaging in semi-structured interviews with program administrators, participating farmers, and advisory board members. Direct content analysis was used to highlight recurrent themes and emerging lessons in relation to the salient particulars of program physical location, administration framework, delivery of ES, and development and receipt by communities. Our three major findings are: 1) Overall, ALUS has been judged by participants to be a very successful program, whose strength is that it is completely voluntary, non-permanent, and readily adaptable to each location’s environmental conditions, economic funding base, and cultural milieu. 2) One serious shortcoming of all ALUS programs is a general lack of quantifiable data on their ability to increase ES. Instead, environmental benefits are either assumed or based on the idea that the areal extent of enrolled land is the sole measure of its environmental worth. 3) It may be that the social impact of ALUS is its greatest success. In this regard, for farmers, it is the process of engaging in land-use decision making and the recognition of their role as environmental stewards that is a bigger motivation for participating in an ALUS program than the modest financial incentives which they receive.
文摘A research project on interaction between agroecosystems and global change has been accepted as a Category Ⅰ contribution to IGBP-GCTE (International Geosphere-Biosphere Programme-Global Change & Terrestrial Ecosystems) Core Research, the highest-level support GCTE has offered to an individual research project so far. This was confirmed by Prof. Noble, GCTE Chairman, in a letter to Prof. Peng Shaolin, Principal Investigator of
基金supported by the National Natural Science Foundation of China (31171506 and 31071375)
文摘To accurately evaluate the carbon sequestration potential and better elucidate the relationship between the carbon cycle and regional climate change, using eddy covariance system, we conducted a long-term measurement of CO 2 fluxes in the rain-fed winter wheat field of the Chinese Loess Plateau. The results showed that the annual net ecosystem CO 2 exchange (NEE) was (-71.6±5.7) and (-65.3±5.3) g C m-2 y-1 for 2008-2009 and 2009-2010 crop years, respectively, suggesting that the agro-ecosystem was a carbon sink (117.4-126.2 g C m-2 yr-1). However, after considering the harvested grain, the agro- ecosystem turned into a moderate carbon source. The variations in NEE and ecosystem respiration (R eco ) were sensitive to changes in soil water content (SWC). When SWC ranged form 0.15 to 0.21 m3 m-3, we found a highly significant relationship between NEE and photosynthetically active radiation (PAR), and a highly significant relationship between R eco and soil temperature (T s ). However, the highly significant relationships were not observed when SWC was outside the range of 0.15-0.21 m3 m-3. Further, in spring, the R eco instantly responded to a rapid increase in SWC after effective rainfall events, which could induce 2 to 4-fold increase in daily R eco , whereas the R eco was also inhibited by heavy summer rainfall when soils were saturated. Accumulated R eco in summer fallow period decreased carbon fixed in growing season by 16- 25%, indicating that the period imposed negative impacts on annual carbon sequestration.
基金Supported by Key Natural Science Foundation of Fujian Province(2008J0120)Natural Science Foundation of Fujian Province(2006J0009)+1 种基金Non-profit Program from Science and Technology Department of Fujian Province(2009R10032-1 and 2010R1024-2)Special Fund for the Establishment of S&T Innovation Teams in Fujian Academy of Agricultural Sciences from Financial Department of Fujian Province(STIF-Y01)
文摘Nitrification and denitrification are two key links of nitrogen flow cycle in soil.N2O and N2,generated from biochemical process of nitrogen,can cause not only the nitrogen losses and reduction of nitrogen use efficiency,but also the boosted concentration of greenhouse gases,severely endangering the environment.Accordingly,nitrification-denitrification has been more and more concerned from whether an agricultural view,or an environmental one.Referring to the related literatures published at home and abroad in recent years,we overviewed the denitrification-caused N loss and N2O emission in various agro-ecosystems,and based on which we put forward countermeasures to reduce the denitrification-caused N loss and N2O emission and its research prospects in the future.
基金supported by the National Natural Science Foundation of China (Grant No. 40710019002)the Ministry of Science and Technology of China (Grant No. 2008BAD95B13-1)the Ministry of Education of China for key basic research projects
文摘Topsoil soil organic carbon(SOC) data were collected from long-term Chinese agro-ecosystem experiments presented in 76 reports with measurements over 1977 and 2006.The data set comprised 481 observations(135 rice paddies and 346 dry croplands) of SOC under different fertilization schemes at 70 experimental sites(28 rice paddies and 42 dry croplands).The data set covered 16 dominant soil types found in croplands across 23 provinces of China's Mainland.The fertilization schemes were grouped into six categories:N(inorganic nitrogen fertilizer only),NP(compound inorganic nitrogen and phosphorus fertilizers),NPK(compound inorganic nitrogen,phosphorus and potassium fertilizers),O(organic fertilizers only),OF(combined inorganic/organic fertilization) and Others(other unbalanced fertilizations such as P only,K only,P plus K and N plus K).Relative change in SOC content was analyzed,and rice paddies and dry croplands soils were compared.There was an overall temporal increase in topsoil SOC content,and relative annual change(RAC,g kg-1 yr-1) ranged -0.14-0.60(0.13 on average) for dry cropland soils and -0.12-0.70(0.19 on average) for rice paddies.SOC content increase was higher in rice paddies than in dry croplands.SOC increased across experimental sites,but was higher under organic fertilization and combined organic/inorganic fertilizations than chemical fertilizations.SOC increase was higher under balanced chemical fertilizations with compound N,P and K fertilizers than unbalanced fertilizations such as N only,N plus P,and N plus K.The effects of specific rational fertilizations on SOC increase persisted for 15 years in dry croplands and 20 years in rice paddies,although RAC values decreased generally as the experiment duration increased.Therefore,the extension of rational fertilization in China's croplands may offer a technical option to enhance C sequestration potential and to sustain long-term crop productivity.
文摘Agriculture under changing climate scenario is facing major challenges of water scarcity and resource imbalances.Crop water productivity(WP)may act as an indicator of crop responses to water limitation.Organic amendments such as biochar and manure application to soil are suggested for improving soil quality and reducing water requirements from agricultural sector.However,studies exploring the impact of biochar as sole or in combination with organic and/or chemical fertilizers on WP in dry tropical agro-ecosystems are limited.In this study,we observed the effect of rice-husk ash(RHA,biochar)along with farm-yard manure(FYM)and chemical fertilizers(CF)under varying water conditions on soil hydro-physical properties,yield and WP of wheat crop.Water-filled pore space(WFPS),grain and straw yield,irrigation and total water productivity varied significantly(at P<0.001)at treatment level.Grain and straw yield were found higher under sole and combined CF applied treatments.Sole and combined RHA and FYM amendment improved water holding capacity(WHC)and WFPS,whereas a decrease in crop yield was observed as compared to the control.Irrigation and total water productivity were found higher under combined RHA+FYM and sole CF treatments with reduced water supply(except sole CF)as compared to control and sole RHA treatments with full water irrigation.Crop water productivity was found positively correlated with grain and straw yields,however,significant correlations were not observed with WHC and WFPS.Results indicate that increasing soil hydro-physical properties in silty-loam soil may hinder crop yield and WP under sole biochar applied soils.Overall,the implications of the study would help in devising agro-management practices based on combined application of RHA and FYM with reduced chemical fertilizer and water inputs to mitigate the impacts of climate change without compromising crop yield in the highly vulnerable dry tropical agro-ecosystem of India.Moreover,long-term studies are needed in these ecosystems to identify the appropriate agricultural package for mitigating the forthcoming water scarcity conditions.
基金supported by the National Science & Technology Pillar Program during the 12th Five-year Plan Period (No. 2013BAD11B03)the National Natural Science Foundation of China (Nos. 71573260,71273153,and 71525007)the Basic Scientific Research Fund (No. BSRF201311) for National Nonprofit Institutes from Ministry of Agriculture(MoA),China
文摘Research on carbon cycling has attracted attention from both scientists and policy-makers.Based on material flow analysis,this study systematically budgets the carbon inputs,outputs and balance from 1980 to 2013 for China's agro-ecosystem and its sub-systems,including agricultural land use,livestock breeding and rural life. The results show that from1980 to 2013,both the carbon input and output were growing gradually,with the carbon input doubling from 1.6 Pg C/year in 1980 to 3.4 Pg C/year in 2013,while carbon output grew from 2.2 Pg C/year in 1980 to 3.8 Pg C/year in 2013. From 1980 to 2013,the crop production system in China has remained a carbon source,and the agricultural land uses were also almost all carbon sources instead of carbon sinks. As soil carbon stock plays a very important role in deciding the function of China's agro-ecosystem as a carbon sink or source,practices that can promote carbon storage and sequestration will be an essential component of low carbon agriculture development in China.
文摘农业生态学作为生态学和农业科学的交叉学科,有助于优化传统农业体系和生态农业实践。为厘清国际农业生态学的发展现状和研究趋势,本文借助CiteSpace对2012—2021年Web of Science核心数据库的国际农业生态学论文进行计量分析,研究发现:1)国际农业生态学的热点议题主要是农业生态系统的整体表现及其评价的研究、以生态农业实践为基础的科学研究以及关于生态农业社会运动与社会影响的研究等。2)国际农业生态研究人员在农业生态学领域有很多基础性和创新性研究,主要围绕农业生态转型与生态农业产业形态、生态农业社会运动以及如何调节农业生态系统内部诸生态因子、建构可持续农业生态体系展开。3)国际农业生态学研究的前沿趋势不仅聚焦于涉及自然学科的生物多样性保护、景观生态安全格局、农业种植体系与农业环境污染等内容,还涉及社会管理相关领域的知识型农民培育、农业教育和参与式治理模式等方面。未来国内农业生态学的发展可在立足国情的基础上,加强国际交流合作,同时,紧随国家发展战略,推动新型农业技术的创新发展。
文摘中国北方农牧交错带是我国重要的生态安全屏障之一,面临经济发展与脆弱生态环境保护间的突出矛盾。生态系统服务的定量研究是生态可持续管理的重要科学依据,也是当前的研究热点之一。以北方农牧交错带的核心区域--内蒙古中西部地区为例,结合中高分辨率遥感数据和生物物理模型准确量化了2000-2018年关键生态系统服务,基于Getis-Ord G*方法分析了生态系统服务的空间格局,考虑地理数据的空间自相关性选取了空间回归模型探索其影响因子。结果表明:(1)净初级生产力(NPP,Net primary productivity)、土壤水蚀控制服务(SC,Soil conservation)、产水量(WY,Water yield)及三层土壤含水量(SM1,Soil moisture of top layer;SM2,Soil moisture of middle layer;SM3,Soil moisture of bottom layer)在东部较高,防风固沙服务(SF,Sand fixation)在南部和西部较高;(2)以上生态系统服务受气候变化、景观格局、地形和土壤条件等综合影响,不同影响因素对生态系统服务的作用存在差异。NPP受森林景观格局和归一化植被指数的影响最为显著;WY、SM1、SM2、SM3及SC受降水量的影响较为显著;风速和表层土壤砂粒含量对SF影响最为显著。研究结果可以为优化景观格局和土地系统,缓解中国北方农牧交错带的社会-生态矛盾提供科学依据和案例参考。
