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Coupling Coordination Analysis of Cropland Intensification and Agroecosystem Services:Evidence from Loess Plateau in Shaanxi Province,China
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作者 FU Shaowu FU Mengyu QIU Menglong 《Chinese Geographical Science》 SCIE CSCD 2024年第3期401-419,共19页
One of the greatest challenges in the agroecosystem is to improve cropland intensification while preserving agroecosystem services.While many studies have investigated the effect of cropland intensification on agroeco... One of the greatest challenges in the agroecosystem is to improve cropland intensification while preserving agroecosystem services.While many studies have investigated the effect of cropland intensification on agroecosystem service,the interactive coupling and coordination among these factors remain largely unexplored.In view of this,this study performed a case study of the Loess Plateau in Shaanxi Province,China and constructed comprehensive evaluation models to quantify the cropland intensification and agroecosystem service in this area.Balance analysis and the coupling coordination degree model were used to evaluate the interactive relationship between cropland intensification and agroecosystem service,and statistical analysis and spatial autocorrelation were used to analyze the spatial characteristics and potential mechanism of the coupling coordination.Results show that both the cropland intensification and agroecosystem service in the study area were relatively low yet gradually increased from 2000 to 2020.Agroecosystem service lag was identified as the dominant unbalanced development type.Improving the supply capacity of agroecosystem services plays a key role in the balanced development of cropland in the Loess Plateau.The coupling coordination degree between cropland intensification and agroecosystem service ranges from basic coordination to serious incoordination.Therefore,cropland intensification practices in the area should be optimized to enhance this coordination degree.An upward trend was also observed in the coupling coordination degree from2000 to 2020.The withdrawal of marginal cropland in the Grain for Green program is one of the most important reasons for this trend,especially for the northern region.Around 83.6%of the high-high clusters are concentrated in the southern region of the Loess Plateau,whereas 70.5%of the low-low clusters are distributed in the northern region.These clustering characteristics are mainly attributed to the environmental suitability of these areas for agriculture and their degree of economic development. 展开更多
关键词 cropland intensification agroecosystem services balance analysis coupling coordination degree Loess Plateau China
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Typology and Agroecology of Agroecosystems in Vegetation Dynamics in the Ecotones of the Mbam and Inoubou
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作者 Alex Bruno Dong Etchike Lucie Félicité Temgoua +3 位作者 Bertine Tiokeng Marie Caroline Momo Solefack Martin Benoit Ngassoum Pierre Marie Mapongmetsem 《Open Journal of Forestry》 2024年第1期42-66,共25页
Agroforestry systems strongly characterize the Cameroonian agrarian landscape. Agroforests are among those structuring the ecotones of Mbam and Inoubou in the Central Cameroon region. Numerous works on agroecosystems ... Agroforestry systems strongly characterize the Cameroonian agrarian landscape. Agroforests are among those structuring the ecotones of Mbam and Inoubou in the Central Cameroon region. Numerous works on agroecosystems of Central and South Cameroon, few have come out contribution of the structure of these traditional systems in the dynamics of the vegetation of these forest-savannah ecotones. The present contribution has the overall objective of demonstrating the structural efficiency of agroforests the dynamics of ecotone vegetation, but also in the conservation of biodiversity. To do this, a participatory analysis was carried out with 56 farmers distributed in the five villages of Makénéné. Botanical inventories supplemented socio-economic household surveys. The data collected was subjected to various analyzes (univariate test, analysis of variance, multivariate test, PCA, CAH). The results reveal that 55.2% of agroforests are less than 15 years old and those with an area greater than 1500 m<sup>2</sup> predominate (33%). They are mainly young with generally small surface areas. The horizontal structure reveals that the largest diameter classes are those of [20 - 30 cm[ and [10 - 20 cm[ with a very low rate of basal area. Agroforests with trees over 10 m high are dominant in five villages of Makénéné. Two types of structural profiles characterize the agroforestry flora of the area, namely intensive pluristratified home gardens on savannah and intensive pluristratified agroforests under forest-savannah transition vegetation. Principal Component Analysis (PCA) and Ascending Hierarchical Clustering (HAC) show three Agroforest Clusters each. The PCA distribution reveals that woody biomass (Y) is strongly correlated with tree diameter (DBH) and significantly with height (Cluster 2). The age (AAG) (Cluster 1) of these agroforests, on the other hand, remains independent of the density (DST) of these trees (Cluster 3). The agroforests in the Nyokon, Carrière and Mocksud villages are the most effective in terms of conserving woody diversity while the agroforests of the Kinding ndé and Nyokon villages are more efficient in the reforestation processes. These results could be considered as effective and quantifiable tools for the certification of numerous cash crops such as cocoa and coffee, which will make it possible to valorize this local knowledge in terms of scientific and in the development of various programs and writing of technical notes. 展开更多
关键词 Agroforests agroecosystem Center Cameroon Dynamics AGROECOLOGY TYPOLOGY
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Climate Change Impacts on Agroecosystems in China:Processes,Mechanisms and Prospects
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作者 BAO Lun YU Lingxue +3 位作者 LI Ying YAN Fengqin LYNE Vincent REN Chunying 《Chinese Geographical Science》 SCIE CSCD 2023年第4期583-600,共18页
Building a more resilient response system to climate change for sustainable development and reducing uncertainty in China’s food markets,requires access to historical research gaps and mapping future research progres... Building a more resilient response system to climate change for sustainable development and reducing uncertainty in China’s food markets,requires access to historical research gaps and mapping future research progress for decision making.However,the lack of quantitative and objective analyses to ensure the stability and development of agroecosystems increases the complexity of agro-climatic mechanisms,which leads to uncertainty and undesirable consequences.In this paper,we review the characteristics of climate change in China(1951–2020),reveal the mechanisms of agroecosystem structure in response to climate,and identify challenges and opportunities for future efforts in the context of research progress.The aim is to improve the scientific validity and relevance of future research by clarifying agro-climatic response mechanisms.The results show that surface temperature,precipitation,and frequency of extreme weather events have increased to varying degrees in major agricultural regions of China in 1951–2020.And they have strong geographic variation,which has resulted in droughts in the north and floods in the south.Moreover,climate change has complicated the mechanisms of soil moisture,Net Primary Productivity(NPP),soil carbon pool,and crop pest structure in agroecosystems.This lends to a reduction in soil water holding capacity,NPP,soil carbon content,and the number of natural enemies of diseases and insects,which in turn affects crop yields.However,human interventions can mitigate the deterioration of these factors.We have also realized that the methodology and theory of historical research poses a great challenge to future agroecosystem.Historical and projected climate trends identified current gaps in interdisciplinary integration and multidisciplinary research required to manage diverse spatio-temporal climate change impacts on agroecosystems.Future efforts should highlight integrated management and decision making,multidisciplinary big data coupling,and numerical simulations to ensure sustainable agricultural development,ecological security,and food security in China. 展开更多
关键词 climate change agroecosystem Net Primary Productivity(NPP) soil carbon pool risk management crop yield
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Soil Organic Carbon Stock and Soil Quality under Four Major Agroecosystems in the Eastern Flank of Mount Bambouto (West-Cameroon)
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作者 Ade Linda Wijungbwen Cedrick Nguemezi +1 位作者 Duchel Ivilin Voulemo Djeuhala Paul Tematio 《Journal of Geoscience and Environment Protection》 2023年第9期40-53,共14页
Assessing soil organic carbon stock (SOCS) and soil quality (SQ) helps design better agricultural practices to improve environmental sustainability and productivity. The purpose of the study is to assess SOCS and soil... Assessing soil organic carbon stock (SOCS) and soil quality (SQ) helps design better agricultural practices to improve environmental sustainability and productivity. The purpose of the study is to assess SOCS and soil quality SQ in the main agroecosystems (AES) of the eastern flank of Mount Bambouto (West, Cameroon). Using multiple statistics tests and principal component analysis (PCA), SOCS and Soil Quality Index (SQI) were computed for each AES. SOCS and SQI were computed based on soil chemical properties and analysis of variance. Topsoil samples (0 - 30 cm) were collected in a different AES and analyzed in the laboratory. The four AES identified and selected are cultivated land (CL), forest areas (FA), mixed areas (MA), and bush areas (BA). Further, multiple comparison tests were used to compare soils from different AES. PCA was used to select the most appropriate indicators that control SOCS and SQ. Several soil properties showed high to very high coefficient of variation within the AES. Organic matter (OM) was significantly high in FA. SOCS and SQ differ significantly (p = 0.000) between the AES. The study further indicates that the main variables controlling SQ within the eastern flank of Mount Bambouto are OM, pHw, N, C/N, and CEC. While the main soil parameters controlling SOCS are OM, OC, BD, C/N, S, and pHKCl. 展开更多
关键词 Soil Organic Carbon Stock Soil Quality agroecosystemS Principal Component Analysis Mount Bambouto
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Hierarchical responses of soil organic and inorganic carbon dynamics to soil acidification in a dryland agroecosystem,China 被引量:1
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作者 JIN Shaofei TIAN Xiaohong WANG Hesong 《Journal of Arid Land》 SCIE CSCD 2018年第5期726-736,共11页
Soil acidification is a major global issue of sustainable development for ecosystems. The increasing soil acidity induced by excessive nitrogen (N) fertilization in farmlands has profoundly impacted the soil carbon ... Soil acidification is a major global issue of sustainable development for ecosystems. The increasing soil acidity induced by excessive nitrogen (N) fertilization in farmlands has profoundly impacted the soil carbon dynamics. However, the way in which changes in soil pH regulating the soil carbon dynamics in a deep soil profile is still not well elucidated. In this study, through a 12-year field N fertilization experiment with three N fertilizer treatments (0, 120, and 240 kg N/(hm-2·a)) in a dryland agroecosystem of China, we explored the soil pH changes over a soil profile up to a depth of 200 cm and determined the responses of soil organic carbon (SOC) and soil inorganic carbon (SIC) to the changed soil pH. Using a generalized additive model, we identified the soil depth intervals with the most powerful statistical relationships between changes in soil pH and soil carbon dynamics. Hierarchical responses of SOC and SIC dynamics to soil acidification were found. The results indicate that the changes in soil pH explained the SOC dynamics well by using a non-linear relationship at the soil depth of 0-80 cm (P=0.006), whereas the changes in soil pH were significantly linearly correlated with SIC dynamics at the 100-180 cm soil depth (P=0.015). After a long-term N fertilization in the experimental field, the soil pH value decreased in all three N fertilizer treatments. Furthermore, the declines in soil pH in the deep soil layer (100-200 cm) were significantly greater (P=0.035) than those in the upper soil layer (0-80 cm). These results indicate that soil acidification in the upper soil layer can transfer excess protons to the deep soil layer, and subsequently, the structural heterogeneous responses of SOC and SIC to soil acidification were identified because of different buffer capacities for the SOC and SIC. To better estimate the effects of soil acidification on soil carbon dynamics, we suggest that future investigations for soil acidification should be extended to a deeper soil depth, e.g., 200 cm. 展开更多
关键词 soil acidification deep soil calcium carbonate generalized additive model (GAM) agroecosystem soilorganic carbon soil inorganic carbon
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Assessment of soil quality using soil organic carbon and total nitrogen and microbial properties in tropical agroecosystems 被引量:1
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作者 Maruf Kajogbola Adebayo Adeboye Abdullahi Bala +3 位作者 Akim Oserhien Osunde Anthony Ozoemenam Uzoma Ayo Joshua Odofin Baba Abubakar Lawal 《Agricultural Sciences》 2011年第1期34-40,共7页
Assessment of soil quality is an invaluable tool in determining the sustainability and environmental impact of agricultural ecosystems. The study was conducted to assess the quality of the soils under arable cultivati... Assessment of soil quality is an invaluable tool in determining the sustainability and environmental impact of agricultural ecosystems. The study was conducted to assess the quality of the soils under arable cultivation, locally irri-gated and non-irrigated, forestry plantations of teak (Tectona grandis Lin.) and gmelina (Gme- lina arborea Roxb.), and cashew (Anacardium occidentale Lin.) plantation agro ecosystems using soil organic carbon (SOC), soil total ni-trogen (STN) and soil microbial biomass C (SMBC) and N (SMBN) at Minna in the southern Guinea savanna of Nigeria. Soil samples were collected from soil depths of 0-5 cm and 5-10 cm in all the agro ecosystems and analyzed for physical, chemical and biological properties. All the agro ecosystems had similar loamy soil texture at both depths. The soils have high fer-tility status in terms of available phosphorus and exchangeable calcium, magnesium and po- tassium. The irrigated arable land had significantly (P 6.6 suggesting fungal domination in all the agroecosystems. The forestry plantation soils had higher SMBC and SMBN as a per-centage of SOC and STN respectively than the cultivated arable land soils. Burning for clearing vegetation and poor stocking of forestry planta-tions may impair the quality of the soil. The study suggests that the locally irrigated agro- ecosystem soil seems to be of better quality than the other agroecosystem soils. 展开更多
关键词 agroecosystemS MICROBIAL BIOMASS SOIL Organic Carbon SOIL Total Nitrogen TROPICAL
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Collembolan Density and Diversity in a Forest and an Agroecosystem 被引量:1
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作者 D. Paul A. Nongmaithem L. K. Jha 《Open Journal of Soil Science》 2011年第2期54-60,共7页
Collembola, commonly called “springtails” are wingless soft-bodied hexapods that are usually between 1 and 3 millimetres in length and occur in varying habits such as, soil surface and litter, under rocks or the bar... Collembola, commonly called “springtails” are wingless soft-bodied hexapods that are usually between 1 and 3 millimetres in length and occur in varying habits such as, soil surface and litter, under rocks or the bark of trees. The great majority develop in soil, feeding on fungi, bacteria, algae and decaying plant matter, and along with other soil fauna constitute the decomposer community. The present study examines the diversity, density, and seasonal variation patterns of collembolan fauna under different intensities of disturbance, as evidenced in a forest and an agroecosystem. Results indicate that both densities and diversity of collembola was higher in the forest than in the agroecosystem. Seasonal fluctuation exhibited an increase from spring to summer and autumn and a decrease during winter. The coorelation patterns with different chemo-edaphic factors did not show any specific trend.Indices of diversity and significant correlation values are discussed in light of landuse. 展开更多
关键词 COLLEMBOLA BIODIVERSITY FOREST agroecosystem
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Agroecosystem functional assessment and its difficulties
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作者 CAOZhi-Ping RichardDawson 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第3期404-407,共4页
Agroecosystem functional assessment indicators provide a necessary bridge between decision makers and scientists. The development of acceptable indicators, however, remains a difficult task because the current knowle... Agroecosystem functional assessment indicators provide a necessary bridge between decision makers and scientists. The development of acceptable indicators, however, remains a difficult task because the current knowledge and understanding of ecosystems is not sufficient to allow an objective assessment of all ecosystem functions. These difficulties were summarized from three perspectives. First, there are difficulties in individual function assessment. Of the four functions associated with agroecosystems energy flow, materials cycling, information flow and value flow data on material cycling and information flow remain difficult to obtain and the indicators relatively immature. Secondly, there are difficulties of integration. During the assessment process, the integration of the agroecosystem functions remains the biggest obstacle. Until now, there has been no practical or effective methodology established to resolve the problem. At present, the makeshift approach has been to weight the various indicators and then add them together. Thirdly, there is the problem of obscure concepts and concept confusion. When assessments of agroecosystems are conducted, concepts such as structure, function, benefit, and resource utilization are used extensively. To date, no logical relationship(either real or implied) has been developed between any of these concepts. Are they causes and results such that the relationship between them is linear, or are they independent from one another such that the relationship is parallel? Thus far, the essence of this question is yet to be explored. 展开更多
关键词 functional assessment INDICATORS agroecosystemS ecological benefit
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Arbuscular Mycorrhizal (AM) Diversity in Prosopis cineraria (L.) Druce Under Arid Agroecosystems
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作者 Neelam Verma Jagadish Chandra Tarafdar +1 位作者 Krishna Kant Srivastava Jitendra Panwar 《Agricultural Sciences in China》 CAS CSCD 2008年第6期754-761,共8页
Arbuscular mycorrhizal (AM) fungi associated with Prosopis cineraria (Khejri) were assessed for their qualitative and quantitative distribution from eight districts of Rajasthan. A total of three species of Acaulo... Arbuscular mycorrhizal (AM) fungi associated with Prosopis cineraria (Khejri) were assessed for their qualitative and quantitative distribution from eight districts of Rajasthan. A total of three species of Acaulospora, one species of Entrophospora, two species of Gigaspora, twenty-one species of Glomus, seven species of Sclerocystis and three species of Scutellospora were recorded. A high diversity of AM fungi was observed and it varied at different study sites. Among these six genera, Glomus occurred most frequently. Glomus fasciculatum, Glomus aggregatum, and Glomus mosseae were found to be the most predominant AM fungi in infecting Prosopis cineraria. Acaulospora, G. fasciculatum, Sclerocystis was found in all the fields studied, while Scutellospora species were found only in few sites. A maximum of thirty-six AM fungal species were isolated and identified from Jodhpur, whereas only thirteen species were found from Jaisalmer. Spores of Glomusfasciculatum were found to be most abundant under Prosopis cineraria. 展开更多
关键词 arbuscular mycorrhizae arid agroecosystems DIVERSITY Prosopis cineraria
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Assessment of the Regime of Functioning Agroecosystems Depending on the Climate and Technogenic Pollution of the Soils
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作者 Lubov V. Pomazkina Lada G. Sokolova Yulia V. Semenova 《Natural Science》 2014年第15期1219-1227,共9页
Some results of monitoring (for the period from 1992 to 2005) related to transformations of carbon in agroecosystems of Baikal Siberia (Russia) characterized by unpolluted grey forest soils as well as the soils techno... Some results of monitoring (for the period from 1992 to 2005) related to transformations of carbon in agroecosystems of Baikal Siberia (Russia) characterized by unpolluted grey forest soils as well as the soils technogenically polluted with heavy metals are discussed with use the unique approach to integrated assessment of the agroecosystem’s functioning regime. The peculiarities of accumulation of carbon in soil microbial biomass and CO2 emission during the years differing in climate conditions are demonstrated. Analysis of formation of net-mineralized and (re)immobilized carbon is conducted, their ratio being used for the purpose of assessment of the level of influence upon the agroecosystem. The agroecosystems having technogenically polluted soils are characterized by processes of the soil microbial biomass reduction and by an obvious increase of CO2 emission into the atmosphere. Negative changes, which are bound up with carbon transformation, are intensified under unfavorable climate conditions. Intensification of processes of carbon net mineralization and, vice versa, lowering the intensity of processes related to carbon (re)immobilization (especially under the effect of soil pollution and climate changes) provoke instability of the agroecosystem and cause formation of a new regime of its functioning. 展开更多
关键词 agroecosystemS REGIME of FUNCTIONING Integral ASSESSMENT Technogenic POLLUTION CLIMATE Changes
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Long-Term Drainage and Nitrate Leaching below Well-Drained Continuous Corn Agroecosystems and a Prairie
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作者 Kevin C. Masarik John M. Norman Kristofor R. Brye 《Journal of Environmental Protection》 2014年第4期240-254,共15页
Many studies have evaluated nitrate-N leaching from tile-drained agricultural soils, but little longterm research has been performed on well-drained soils commonly throughout the Midwest. Equilibrium tension lysimeter... Many studies have evaluated nitrate-N leaching from tile-drained agricultural soils, but little longterm research has been performed on well-drained soils commonly throughout the Midwest. Equilibrium tension lysimeters installed at a depth of 1.4 m were used to measure year-round (12 month) nitrate-N leaching below chisel-plow (CP) and no-tillage (NT) continuous corn (Zea mays L.) agroecosystems to determine the potential effects of common agricultural practices on subsurface water quality. The corn systems were fertilized at a rate of 10 kg N ha-1 of starter fertilizer and 180 kg N ha-1 as NH4NO3. For comparison, nitrate-N leaching from a natural ecosystem was performed on a nearby prairie restoration (PR). Drainage, nitrate-N leaching loss, and flow-weighted mean nitrate-N concentrations for 8 years of data (1996-2003) are reported for the CP, NT and PR ecosystems. Results show that 52%, 37%, 16% of cumulative precipitation was collected as drainage, while 18%, 19%, 0.5% of the total N input was leached as nitrate-N in the CP, NT, and PR, respectively. Nearly three-quarters of the total nitrate-N was leached from each ecosystem during the period from 1 April to 30 June. The 8-yr, flow-weighted mean nitrate-N concentration measured in leachate was 9.5, 12.2 and -1 for the CP, NT and PR treatments. Annual drainage volumes and nitrate-N leaching losses were highly variable, stressing the importance of long-term studies capable of measuring year-round drainage for understanding N leaching dynamics and evaluating effects of cropping practices on potential groundwater quality. 展开更多
关键词 NITRATE LEACHING Flow-Weighted Mean Concentration Maize agroecosystemS PRAIRIE ECOSYSTEM
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Effects of Management Practices on Agronomic Parameters in Cocoa Agroecosystems at Peripheral Zone of Ebo Forest Reserve, Littoral Region, Cameroon
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作者 Ofundem Tataw Ojong Enow Andrew Egbe +2 位作者 Joseph-Marie Ondoua Tina Fongod Raymond Ndip Nkongho 《Agricultural Sciences》 CAS 2022年第10期1151-1175,共25页
The study was carried out to assess the effect of management practices on agronomic parameters of cocoa agroecosystems in the peripheral zone of Ebo Forest Reserve. Purposive random sampling was conducted to establish... The study was carried out to assess the effect of management practices on agronomic parameters of cocoa agroecosystems in the peripheral zone of Ebo Forest Reserve. Purposive random sampling was conducted to establish experimental plots on the farms of willing farmers. Demonstration plots were established and agronomic parameters were monitored for “farmers’ practice (FP) and integrated crop pest and disease management (ICPM) practice” using indicators of Cocoa agro-ecosystem analysis (AESA). The FP and ICPM treatments were replicated in ten sites. From AESA records of agronomic parameters, the “observe, learn, decide and act” (OLDA) model was implemented in the ICPM treatments only. The effects of management practices were analyzed using a two-way analysis of variance (ANOVA), and treatment means compared using Turkey’s T-test at 5% probability. Results of ANOVA between the two Management practices showed that over 50% of the response variables were statistically significant. Means separated through GLM ANOVA with Tukey pairwise comparisons at α = 0.05 showed that 14 (53.8%) out of 26 response variables monitored were statistically significant between the two management practices. Pruning, shade management, phytosanitary harvest, rational use of pesticides, farm sanitation, pod harvesting, breaking, fermentation of beans and drying were regular in the ICPM treatment and time-bound in the FP treatment. The average total production varied from 385.83 kg/ha in FP treatment to 572.8 kg/ha in the ICPM treatment, still below the average standard of 1000 kg/ha. The OLDA model applied in ICPM treatment following AESA is a relevant tool to enhance sustainability in the management of cocoa agroecosystems. Farmers should be sensitized and trained on appropriate farm management techniques and enhance access to extension services as well as make available improved and grafted planting materials to ensure appropriate productivity levels. 展开更多
关键词 agroecosystem Agronomic Parameters Cocoa Management Practices
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Heavy Metal Levels and Potential Ecological Risks Assessed at an Agroecosystem Site in Tropical Region
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作者 Luc Kalendele Lundemi Stéphanie Salumu Neema +7 位作者 Emmanuel Kazinguvu Atibu Crispin Kyela Mulaji Thierry Tabou Tangou Camille Ipey Nsimanda Robert Bueya Suami Marie Onokoko Esako Dieudonné Eyul’Anki Musibono Fernando Piedade Carvalho 《Journal of Geoscience and Environment Protection》 2022年第9期42-60,共19页
The concentrations and distribution of thirteen metals and metalloids were investigated in soils, sediments, and two biological matrices (the fish Clarias gariepisnis and the earthworm Pontoscolex corethrurus) from th... The concentrations and distribution of thirteen metals and metalloids were investigated in soils, sediments, and two biological matrices (the fish Clarias gariepisnis and the earthworm Pontoscolex corethrurus) from the CECOMAF agroecosystem, in Kinshasa, Democratic Republic of the Congo, in order to assess the impact of anthropogenic activities. The results revealed high concentrations of heavy metals, such as Cu, Zn, As, Cd, Pb, and Hg all above values recommended by sediment quality guidelines and their probable effect levels on biota. According to the calculated Enrichment Factor, soil and sediments ranked from moderately to heavily polluted by Cu, Zn, Cd, Pb and Hg. The Contamination Degree and other ecological risk indices indicated very high contamination and very high ecological risks posed by Cd and Hg, respectively. The Geoaccumulation Index indicated that current metal concentrations in the agroecosystem originated from anthropogenic activities, while the Spearman correlation matrix values indicated that Hg could originate from different sources and pathways than the other metals. It was concluded that metals from unchecked anthropogenic activities have negatively impacted agricultural activities and fish production at the CECOMAF agroecosystem. Action to reduce the contamination level and the ecological risks by remediating and preventing metal pollution in the CECOMAF agroecosystem site is recommended. 展开更多
关键词 agroecosystem Site Heavy Metals SOIL SEDIMENT Ecological Risk Clarias gariepisnis Pontoscolex corethrurus
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Ecosystem Services in Differently Used Agroecosystems along a Climatic Gradient in Slovakia
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作者 Jarmila Makovnikova Boris Palka +3 位作者 Milos Siran Beata Houskova Radoslava Kanianska Miriam Kizekova 《Open Journal of Ecology》 2018年第12期623-645,共23页
For analysis and evaluation of potential of agroecosystem (arable land and grassland) services (provisioning, regulating and cultural) in Slovakia we have created a mapping unit combining these input layers: slope top... For analysis and evaluation of potential of agroecosystem (arable land and grassland) services (provisioning, regulating and cultural) in Slovakia we have created a mapping unit combining these input layers: slope topography, soil texture and landuse in four climatic regions. Evaluated potential of agroecosystem services was categorised into five categories (very low, low, medium, high and very high). Our results show that climate has the most significant impact on agroecosystem services. Warm, dry lowland region has a higher potential of provisioning services, regulation of water regime, filtration of pollutants and control of soil erosion in comparison to moderately warm and cold regions. In moderate cold region, more than 90% of the total area of arable land has low potential of water regime regulation and cleaning potential (immobilization of risk elements). In the moderate warm climatic region, there is a high share of categories of low and moderate potential of provisioning services and low and moderate potential of water regime regulation. Majority of the total area of warm climatic region belongs to the categories of moderate to high potential of provisioning services and high potential of regulation of water regime. In this climatic zone low potential categories of risk elements immobilization are present in more than 65% of the arable land total area. On the other hand, in very warm climatic zone, more than 89% of the total area of arable land belongs to the category with a very high cleaning (buffering) potential. Potential of natural conditions for recreation is higher only in moderate cold and moderate warm climatic zones with a higher proportion of area of grassland agroecosystems and protected areas NATURA 2000. Moreover, the methodology developed in this paper is replicable and could be applied by planners in the case that they are proficient in geographical information systems. 展开更多
关键词 agroecosystem Services Climatic Zone MAPPING Trade-Offs SYNERGIES
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Differences in Soil Microbial Biomass and Activity for Six Agroecosystems with a Management Disturbance Gradient 被引量:11
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作者 ZHANGWei-Jian FENGJin-Xia +1 位作者 J.WU K.PARKER 《Pedosphere》 SCIE CAS CSCD 2004年第4期441-448,共8页
Different management practices in six agroecosystems located near Goldsboro, NC, USA were conducted including a successional field (SU), a plantation woodlot (WO), an integrated cropping system with animals (IN), an o... Different management practices in six agroecosystems located near Goldsboro, NC, USA were conducted including a successional field (SU), a plantation woodlot (WO), an integrated cropping system with animals (IN), an organic farming system (OR), and two cash-grain cropping systems employing either tillage (CT) or no-tillage (NT) to examine if and how microbial biomass and activity differ in response to alterations in disturbance intensity from six land management strategies. Results showed that soil microbial biomass and activity differed, with microbial activity in intermediately disturbed ecosystems (NT, OR, IN) being significantly higher (P < 0.01) than systems with either high or low disturbance intensities. There was also a significant and a highly significant ecosystem effect from the treatments on microbial biomass C (MBC) (P < 0.05) and on microbial activity (respiration) (P < 0.01), respectively. Multiple comparisons of mean respiration rates distinctly separated the six ecosystem types into three groups: CT < NT, SU and WO < OR and IN.Thus, for detecting microbial response to disturbance changes these results indicated that the active component of the soil microbial community was a better indicator than total biomass. 展开更多
关键词 农业系统 碳保持力 干扰强度 单位面积微生物数量 土壤微生物活性
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Nutrient Cycling and Balance in Red Soil Agroecosystem and Their Management 被引量:8
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作者 HE YUANQIU and LI ZHIMING.(Institute of Soil Science, the Chinese Academy of Sciences, P.O. Box 821, Nanjing 210008 China) 《Pedosphere》 SCIE CAS CSCD 2000年第2期107-116,共10页
An experiment was conducted in a red soil derived from Quaternary red clay in the Ecological ExperimentStation of Red Soil, the Chinese Academy of Sciences, located in Yingtan (28° 15′ 30″ N, 116° 55′ 30... An experiment was conducted in a red soil derived from Quaternary red clay in the Ecological ExperimentStation of Red Soil, the Chinese Academy of Sciences, located in Yingtan (28° 15′ 30″ N, 116° 55′ 30″E), Jiangxi Province. The results show that the major ways of nutrient loss are leaching and nitrogenvolatilization. Rationalizing crop distribution, stimulating nutrient recycling, and improving internal nutrientflow are effective measures to decrease nutrient loss and to promote nutrient utilization efficiency. Theimportant ways of regulating nutrient cycling and balance in the agroecosystem of the red soil are to establishoptimal eco-agricultural models, practice balanced fertilization and combine the cropping system with thelivestock system. 展开更多
关键词 红壤农业生态系统 养分循环 施肥 家畜 庄稼
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Comparison of Soil Biota Between Organic and Conventional Agroecosystems in Oregon, USA 被引量:2
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作者 WUShan-Mei HUDun-Xiao E.R.INGHAM 《Pedosphere》 SCIE CAS CSCD 2005年第3期395-403,共9页
Soil samples at 0-10 cm in depth were collected periodically at paired fields in Corvallis, Oregon, USA to compare differences in soil microbial and faunal populations between organic and conventional agroecosystems. ... Soil samples at 0-10 cm in depth were collected periodically at paired fields in Corvallis, Oregon, USA to compare differences in soil microbial and faunal populations between organic and conventional agroecosystems. Results showed that the organic soil ecosystem had a significantly higher (P < 0.05) average number or biomass of soil bacteria; densities of flagellates, amoebae of protozoa; some nematodes, such as microbivorous and predaceous nematodes and plant-parasitic nematodes; as well as Collembola. Greater numbers of Rhabditida (such as Rhabditis spp.), were present in the organic soil ecosystem while Panagrolaimus spp. were predominant in the conventional soil ecosystem. The omnivores and predators of Acarina in the Mesostigmata (such as Digamasellidae and Laelapid), and Prostigmata (such as Alicorhaiidae and Rhagidiidae), were also more abundant in the organic soil ecosystem. However, fungivorous Prostigmata (such as Terpnacaridae and Nanorchestidae) and Astigmata (such as Acarida) were significantly higher (P < 0.05) in the conventional soil ecosystem, which supported the finding that total fungal biomass was greater in the conventional soil ecosystem. Seansonal variations of the population depended mostly on soil moisture condition and food web relationship. The population declined from May to October for both agroecosystems. However, higher diversities and densities of soil biota survived occurred in the organic soil ecosystem in the dry season. 展开更多
关键词 土壤生物区 农业生态系统 俄勒冈州 美国 有机质 微生物种群
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Nitrogen cycle model of agroecosystem in the karst region of Guizhou Province 被引量:1
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作者 CHEN Ye LIAN Bin 《Chinese Journal Of Geochemistry》 EI CAS 2010年第4期464-470,共7页
According to the transport theory of soil solutes and the conditions of soil,geology and climate in the karst region of Guizhou Province,a numerical simulation model of edaphic nitrogen element transport under field c... According to the transport theory of soil solutes and the conditions of soil,geology and climate in the karst region of Guizhou Province,a numerical simulation model of edaphic nitrogen element transport under field conditions is initially established.In this model,NO-3 and NH+4 are regarded as soil solutes.Transformation mechanisms such as biological release,bio-immobilization,ammonium adsorption-desorption,nitration-denitrification and factors of crop root uptaking are considered in this model.It is hoped that the data from this model could directly be used to guide agricultural production in this region and offer feasible ways to improve the use of nitrogen element,sustainable development of agriculture in karst mountainous areas and natural environment. 展开更多
关键词 生态系统模型 农业生产 贵州省 喀斯特地区 土壤溶质运移 氮循环 农业可持续发展 反硝化作用
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Farmer's Adaptive Strategies on Land Competition between Societal Outcomes and Agroecosystem Conservation in the Purple-soiled Hilly Region,Southwestern China 被引量:2
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作者 TANG Qiang BAO Yuhai +2 位作者 HE Xiubin ZHU Bo ZHANG Xinbao 《Journal of Mountain Science》 SCIE CSCD 2012年第1期77-86,共10页
The worldwide extension and intensification of farming during the last century has led to ecosystem degradation and caused a series of environmental problems.Conservation of ecosystem services in agricultural regions ... The worldwide extension and intensification of farming during the last century has led to ecosystem degradation and caused a series of environmental problems.Conservation of ecosystem services in agricultural regions has been implemented by top-down government actions or initiated by resilience scientists in the developed countries,but little attention was paid in the developing countries,especially in some remote mountainous regions.The present paper presents a case study showing how local farmers obtained both maximal societal outcomes and agroecosystem conservation interests in the absence of distinct boundaries between agricultural and protected ecological areas in the densely populated purple-soiled hilly region of southwestern China.The local community(Yanting County) has developed a mosaic agricultural-forestry-fishery-stock breeding system with spatially targeted land uses,diverse agricultural productions and multiple ecological partnerships.It indicates that the local farmers have hereditarily perceived sound strategies on maximizing sustainable societal outcomes and optimizing tradeoffs among macro-market,state policy,new technological facility and ecological reinforcement. 展开更多
关键词 生态系统保护 中国西南地区 农业区域 土地用途 自适应策略 社会 农民 丘陵区
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Agrobiodiversity of Muda Rice Agroecosystem:A Case Study in Largest Granary Area of Malaysia
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作者 Amir Shah Ruddin Md Shah Mashhor Mansor Shahrul Anuar Mohd Shah Che Salmah Mohd Rawi Abu Hassan Ahmad Ibrahim Jaafar 《湿地科学》 CSCD 2008年第1期34-44,共11页
A survey was carried out at the largest rice cultivation area in Peninsular Malaysia,the Muda rice agroecosystem.The main objective of this study was to document the overall biodiversity associated with this unique ag... A survey was carried out at the largest rice cultivation area in Peninsular Malaysia,the Muda rice agroecosystem.The main objective of this study was to document the overall biodiversity associated with this unique agroecosystem by using a combination of sampling techniques in order to record different groups of fauna and flora.The total number of biota recorded and identified from the rice field ecosystem during the study period consisted of 46 species of zooplankton,81 species of aquatic insects,5 species of rodents,7 species of bats,87 species of birds,11 species of fishes and 58 species of weeds.A long-term study should be carried out as more species are expected to be recorded when more of the Muda rice agroecosystem area has been sampled to obtain sufficient information on the Muda rice agrobiodiversity. 展开更多
关键词 土壤生物多样性 水稻 农业生态系统 马来群岛
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