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A New Cultivation Technique of Cangmai 6005 for High Yield in Cangzhou Dry-alkali Land 被引量:1
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作者 Liang YU Weiwei WANG +6 位作者 Liya NIU Wei WANG Li LU Fengzhi WANG Lianpeng WANG Yan WANG Xiujin ZANG 《Asian Agricultural Research》 2018年第2期68-70,共3页
Cangmai 6005 is a national wheat variety approved by Cangzhou Academy of Agriculture and Forestry Sciences,which has the characteristics of drought resistance,salt tolerance,high yield and stable yield. According to t... Cangmai 6005 is a national wheat variety approved by Cangzhou Academy of Agriculture and Forestry Sciences,which has the characteristics of drought resistance,salt tolerance,high yield and stable yield. According to the characteristics of dry-alkali land in Cangzhou City and the variety characteristics,the new cultivation technique was completed. 展开更多
关键词 Cangmai 6005 dry-alkali land New technique
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Effects of Land Use Change on the Ecosystem Services Value in the Dry-Hot Valley 被引量:1
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作者 ZHOU Hongyi XIONG Donghong +1 位作者 YANG Zhong HE Xiubin 《Wuhan University Journal of Natural Sciences》 CAS 2007年第4期743-748,共6页
The objective of the study reported here was to determine whether LANDSAT TM images could be used to quantify changes in land-use and ecosystem services in Yuanmou County. The sizes of six land use/land cover (LUCC)... The objective of the study reported here was to determine whether LANDSAT TM images could be used to quantify changes in land-use and ecosystem services in Yuanmou County. The sizes of six land use/land cover (LUCC) categories were estimated in Yuanmou County according to the LANDSAT TM images in the summer of 1986 and 2005. Coefficients published by Xie Gaodi and co-workers in 2003 were used to value changes in ecosystem services delivered by each land use/land cover category, and the ecosystem services sensitivity analysis was conducted to determine the effect of manipulating these coefficients on the estimated values. The important results are summarized as followings. (1) The estimated size of cultivated land, pasture land, water area and unused land decreased by 6.39%, 1.35%, 2.25% and 10.67% respectively between 1986 and 2005. By contrast, the estimated size of forest land and construction land increased by about 2.23% and 71.15% respectively between 1986 and 2005. (2) The total ecosystem services value (EVS) of the study area increased from 2 142 132 609.46 yuan to 2 146 416 621.00 yuan, with the net increase of 4 284 011.54 yuan during the 20-year time period. (3) The coefficient sensitivity (CS) of the study are less than unity in all cases (CS 〈 1). This indicates that the total ecosystem values estimated for the study area are relatively inelastic with respect to the ecosystem service coefficients. While this implies that our estimates are robust and the coefficient is reasonable, highly under or over valued coefficients can substantially affect the veracity of estimated changes in ecosystem service values overtime even when the CS are less than unity(CS 〈 1). 展开更多
关键词 land use/land cover ecosystem services value dry-hot valley YUNNAN
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The Impact of Nitrogen-Fixing Bacteria, Iron, and Zinc Foliar Application on Dry Land Yellow Mustard (Brassica juncea) Grain and Oil Production
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作者 Saeid Zehtab Salmasi Haleh Nasiri +2 位作者 Rezvan Heshmati Mohammad Reza Sarikhani Yagoub Raei 《Agricultural Sciences》 2024年第7期719-728,共10页
The study, conducted at the Research Farm of the College of Agriculture, University of Tabriz in 2021, focused on the effects of various nitrogen-fixing bacterial isolates, biofertilizers containing nitrogen and phosp... The study, conducted at the Research Farm of the College of Agriculture, University of Tabriz in 2021, focused on the effects of various nitrogen-fixing bacterial isolates, biofertilizers containing nitrogen and phosphorus, as well as iron and zinc foliar applications on mustard growth under rainfed conditions. The results indicated that biofertilizers, whether used alone or in combination with chemical fertilizers, produced comparable grain and oil outputs compared to chemical fertilizers alone. Additionally, the application of iron and zinc through foliar spraying significantly enhanced both grain and oil production. These findings suggest that integrating nitrogen-fixing bacteria and biofertilizers could reduce reliance on chemical nitrogenous fertilizers, leading to decreased production expenses, improved product quality, and minimized environmental impact. This study highlights the potential for sustainable agricultural practices in dry land farming as a viable alternative to traditional chemical-intensive methods. Substituting chemical nitrogenous fertilizers with nitrogen-fixing bacteria or biofertilizers could result in cost savings in mustard grain and oil production while promoting environmental sustainability. 展开更多
关键词 Nitrogen Fixing Bacteria Yellow Mustard Dry land Farming IRON ZINC Foliar Application
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THE POSSIBILITIES AND REALITIES ON THE REMANAGEMENT OF DESERTIFIED LANDS IN THE TRANSITIONAL ZONE BETWEEN THE DRY-FARMING AREA AND THE GRAZING AREA IN NORTH CHINA
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作者 朱震达 刘恕 杨有林 《Chinese Geographical Science》 SCIE CSCD 1991年第1期32-43,共12页
The desertification process is rapidly developing at present and 61.5% of the land area in the zone are already desertified.Among the desertified lands, 26.9% are seriously desertified, 25% most seriously desertified ... The desertification process is rapidly developing at present and 61.5% of the land area in the zone are already desertified.Among the desertified lands, 26.9% are seriously desertified, 25% most seriously desertified and 47.4% are the lands where desertification is under way. They are caused by over-reclamation for farming, over-grazing, unreasonable collection of firewood,the destruction of vegetation and the misuse of water resources. Under the ecological environment in semi-arid zone,the degraded environment process possesses the ability of restoring to its original status as soon as the interruption of excessive human activities are eliminated. The fencing- and-self-cultivating method is an effective measure adopted universally in semi-arid zone to cure the desertified lands.The desertified lands can be readjusted and controlled easily if other controlling measures are supplemented. The fundamental ways to control desertification are to utilize rationally the resources, to readjust the existing 展开更多
关键词 desertified lands the transitional zone BETWEEN the dry-larming area and the GRAZING area remanagement NORTH China.
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Developmental Tendency of Dry Land Farming Technologies 被引量:10
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作者 SHAN Lun(Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Northwest Sci-Tech University of Agriculture and Forestry, Yangling 712100, P. R . China ) 《Agricultural Sciences in China》 CAS CSCD 2002年第8期934-944,共11页
The developmental tendency of dry land farming technologies in the semiarid area of China were reviewed based on the overview of recent progress in dry land farming researches from China and oversea. It was emphasized... The developmental tendency of dry land farming technologies in the semiarid area of China were reviewed based on the overview of recent progress in dry land farming researches from China and oversea. It was emphasized that conservation tillage, limited irrigation, genetic modification and chemical control are the important aspects for the dry land farming research and development of the future. In addition, some consid- 展开更多
关键词 Dry land farming Conservation tillage Limited irrigation Genetic modification Chemical control
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Spatiotemporal variation of soil organic carbon in the cultivated soil layer of dry land in the South-Western Yunnan Plateau, China 被引量:6
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作者 ZHAO Ji-xia DAI Fu-qiang +2 位作者 HE Shou-jia ZHANG Qing LIU Gang-cai 《Journal of Mountain Science》 SCIE CSCD 2017年第12期2484-2497,共14页
The dynamics of soil organic carbon(SOC)in cropland is one of the central issues related to both soil fertility and environmental safety. However, little information is available at county level regarding the spatiote... The dynamics of soil organic carbon(SOC)in cropland is one of the central issues related to both soil fertility and environmental safety. However, little information is available at county level regarding the spatiotemporal variability of SOC in the southwestern mountainous region of China. Thus, this study aimed to explore spatiotemporal changes of SOC in the cultivated soil layer of dry land in Mojiang County,Yunnan Province, China. Data were obtained from the second national soil survey(SNSS) of 1985 and soil tests for fertilizer application carried out by the Mojiang Agricultural Bureau in 2006. The ANOVA test was applied to determine any significant differences between the datasets, while semivariogram analysis was performed on geostatistics via an ordinary Kriging method in order to map spatial patterns of soil organic carbon density(SOCD). The results revealed that SOCD in the cultivated soil layer significantly decreased from 3.93 kg m^(-2) in 1985 to 2.89 kg m^(-2) in 2006, with a total soil organic carbon stock(SOCS) decrease of 41.54×10~4 t over the same period. SOCS levels fell most markedly in yellow-brown soil at a rate of51.52%, while an increase of 8.70% was found in the analysed latosol. Geostatistical analysis also showed that the recorded changes in SOCD between 1985 and2006 were spatially structured. The decreasing trend might be attributed to the combined action of intense cultivation, major crop residue removal without any protective tillage measures, unreasonable fertilization and natural climatic diversity inducing a large decrease in SOC in the studied cultivated dry land region of Mojiang County. Therefore, management measures such as protective tillage should be undertaken in order to enhance soil C sequestration. 展开更多
关键词 Soil organic carbon Spatiotemporal changes Dry land Cultivated soil layer Yunnan Plateau
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Effects of a Remotely Sensed Land Cover Dataset with High Spatial Resolution on the Simulation of Secondary Air Pollutants over China Using the Nested-grid GEOS-Chem Chemical Transport Model 被引量:1
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作者 LI Mingwei WANG Yuxuan JU Weimin 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第1期179-187,共9页
A number of remotely sensed land cover datasets with spatial resolutions ~〈 1 km have recently become available or are in the process of being mapped. The application of these higher resolution and more up-to-date la... A number of remotely sensed land cover datasets with spatial resolutions ~〈 1 km have recently become available or are in the process of being mapped. The application of these higher resolution and more up-to-date land cover datasets in chemical transport models (CTMs) is expected to improve the simulation of dry deposition and biogenic emissions of non-methane volatile organic compounds (NMVOCs), which affect ozone and other secondary air pollutants. In the present study, we updated the land cover dataset in the nested-grid GEOS-Chem CTM with the 1 km resolution GLC2000 land cover map and examined the resulting changes in the simulation of surface ozone and sulfate over China in July 2007. Through affecting the dry deposition velocities of ozone and its precursors, using GLC2000 in the dry deposition module can decrease the simulated surface ozone by 3% (up to 6 ppb) over China. Simulated surface sulfate shows an increase of 3% in northwestern China and a decrease of 1% in northern China. Applying GLC2000 in the biogenic emissions of the NMVOC module can lead to a 0.5--4.5 ppb increase in simulated surface ozone over East China, mainly driven by the larger cove~:age of broadleaf trees in East China in the GLC2000 dataset. Our study quantifies the large sensitivity to land cover dataset~ with different spatial resolutions and time periods of simulated secondary air pollutants over China, supporting ongoing research efforts to produce high resolution and dynamically updated land cover datasets over China, as well as for the globe. 展开更多
关键词 land cover dry deposition biogenic emissions OZONE SULFATE
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Sorghum as Dry Land Feedstock for Fuel Ethanol Production
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作者 WANG Donghai WU Xiaorong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第4期83-96,共14页
Dry land crops such as sorghums (grain sorghum, promising feedstocks for fuel ethanol production. The major issue sweet sorghum and forage sorghum) have been identified as for using the sweet sorghum as feedstock is... Dry land crops such as sorghums (grain sorghum, promising feedstocks for fuel ethanol production. The major issue sweet sorghum and forage sorghum) have been identified as for using the sweet sorghum as feedstock is its stability at room temperature. At room temperature, the sweet sorghum juice could lose from 40% to 50% of its fermentable sugars from 7 to 14 days No significant sugar content and profile changes were observed in juice stored at refrigerator temperature in two weeks. Ethanol fermentation efficiencies of fresh and frozen juice were high (-93%). Concentrated juice (≥25% sugar) had significantly lower efficiencies and large amounts of fructose left in finished beer; however, winery yeast strains and novel fermentation techniques may solve these problems. The ethanol yield from sorghum grain increased as starch content increased. No linear relationship between starch content and fermentation efficiency was found. Key factors affecting the ethanol fermentation efficiency of sorghum include starches and protein digestibility, amylose-lipid complexes, tannin content, and mash viscosity. Life cycle analysis showed a positive net energy value (NEV) = 25 500 Btu/gal ethanol. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) were used to determine changes in the structure and chemical composition of sorghum biomasses. Dilute sulfuric acid pretreatment was effective in removing the hemicellulose from biomasses and exposing the cellulose for enzymatic hydrolysis. Forage sorghum lignin had a lower syringyl/guaiacyl ratio and its pretreated biomass was easier to hydrolyze. Up to 72% hexose yield and 94% pentose yield were obtained by using a modified steam explosion with 2% sulfuric acid at 140℃ for 30 min and enzymatic hydrolysis with cellulase. 展开更多
关键词 dilute acid pretreatment dry land feedstock FTIR fuel ethanol SORGHUM XRD
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Status and circulation characteristics of soil water in dryland field of southeast Shanxi Province
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作者 Zhong Zhao zhan, Zhao Ju bao, Mei Xu rong Institute of Agrometeorology, Chinese Academy of Agricultural Sciences, Beijing 100081, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第4期27-34,共8页
Based on the observed soil water data from experimental site located in southeast of Shanxi Province, the physical characteristics of soil water, crop effect on soil moisture, and the field water circulation pattern w... Based on the observed soil water data from experimental site located in southeast of Shanxi Province, the physical characteristics of soil water, crop effect on soil moisture, and the field water circulation pattern were studied by using the water balance method. The results suggested that soil water deficit often exists in fields of these areas. From May to June, the amount of water deficit in bare land rises to the maximum (232 8 mm) and falls to the minimum (66 6 mm) from August to September. By comparison, because of crop transpiration, both soil water deficit and dry soil layer in cultivated land are 15 1—40 4 mm more and 20—70 mm deeper respectively than those of bare land. Crops mainly planted in these areas have a relatively weak utilization ability to soil water. Winter wheat has the highest utilization ability to soil water among the crops planted in these areas. The soil water utilization ability of winter wheat is 26 2%—30 6% and winter wheat can use soil water that lies in soil layer below a depth of over 200 cm. Spring corn and millet can only consume soil water with the maximum ability of 13 4% and the deepest layer of 0—50 cm or 0—100cm, which shows that the soil water utilization ability of winter wheat is higher than that of spring crops. After crop is ripe, more than 41% of available soil water remains unused in field. So, increasing soil water storage and improving crop utilization ability to soil water by adopting efficient agrotechnique measures are the main ways for improving agricultural productivity in dry farming areas of Northern China. 展开更多
关键词 soil water field water deficit crop utilization ability to soil water dry land southeast of Shanxi Province.
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Land and Water Use in Rice-upland Crop Rotation Areas in Lower Ili River Basin, Kazakhstan
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作者 SHIMIZU Katsuyuki KITAMURA Yoshinobu +1 位作者 ANZAI Toshihiko KUBOTA Jumpei 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第4期8-13,共6页
The lower Ili River Basin is located in semi-arid area, and the annual rainfall is 177mm. Therefore, the irrigation is inevitable for agriculture. Large-scale irrigated agriculture had been developed since 1960's in ... The lower Ili River Basin is located in semi-arid area, and the annual rainfall is 177mm. Therefore, the irrigation is inevitable for agriculture. Large-scale irrigated agriculture had been developed since 1960's in the lower parts of the river and the total irrigated area is about 32 000 hm2. In the project area, the paddy rice-upland crop rotation has been practiced. Due to the domestic water use for hydropower and agriculture as well as water use among riparian countries, the deficit of water for agriculture in the lower part has been concerned. The authors, therefore, conducted the field survey and water balance analysis of the Akdara irrigation project in the lower Ill River Basin in order to assess the land and water uses. Moreover, the impact of the water use on water environment to the basin was analyzed. The following results were obtained as following (1) the groundwater level in the irrigated district varied from 1.5 m to 3.5 m through year. (2) 1970's groundwater level was drastically raised from 8 m to 3 m and the groundwater had been recharged in this period. (3) Water use efficiency of agriculture, which is the ratio of total evapotranspiration to the total water withdrawal was as low as 0.23. 展开更多
关键词 crop rotation water balance overall irrigation efficiency groundwater fluctuation dry land
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Production Performance of Different Varieties of Oat A vena sativa) in Winter Dry Land of Hunan
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作者 Deng Huifen Wei Zhongshan +1 位作者 Zeng Guozhang Sun Ao 《Animal Husbandry and Feed Science》 CAS 2016年第5期297-300,共4页
The phenological phase, plant height, filler number, nutritional composition, yield and stem/leaf ratio of three oat (Arena sativa) varieties (lines) in winter dry land of Hunan were studied. The result shows that... The phenological phase, plant height, filler number, nutritional composition, yield and stem/leaf ratio of three oat (Arena sativa) varieties (lines) in winter dry land of Hunan were studied. The result shows that the three oat varieties were greatly different in plant height, nutritional composition, yield and stem/leaf ratio. Baiyan 7 had the best performance, with the plant height, tiller number and fresh yield of 101.67cm, 7.6 tiller/plant and 70.15 t/hm2 respectively ; the crude protein content of dry matter of Baiyan 7 was 32.63% ; the leaf weight per tiller of Baiyan 7 accounted for 31.6% of single tiller weight, while those of Baiyan 8 and Baiyan 2 accounted for 31.3% and 29.2%, respectively. The single tiller weight of oat could be estimated/calculated by the model/formula Y = 0.043 7X - 2.89 ( R2 = 0.913 4, P 〈 0.01 ), where Y is the single tiller weight ( g ) and X is the plant height (cm). Comprehensive analysis showed that Baiyan 7 had higher yields and stem/leaf ratio. Thus, Baiyan 7 is more suitable for planting as a winter-spring forage in the winter dry land of Hunan. 展开更多
关键词 Winter dry land of Hunan OAT Production performance Individual development characteristics
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Production of physic nut hybrid progenies and their parental in various dry land
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作者 Maftuchah   Agus Zainudin Hadi Sudarmo 《Agricultural Sciences》 2013年第1期48-56,共9页
Hibridization is one of breeding strategy to increase productivity of crop including physic nut (Jatropha curcas Linn.). This study aimed to obtain information productivity per hectare and seed oil content of 11 numbe... Hibridization is one of breeding strategy to increase productivity of crop including physic nut (Jatropha curcas Linn.). This study aimed to obtain information productivity per hectare and seed oil content of 11 numbers of physic nut hybrids and their parental in four dry lands. The research was conducted in four dry land: Kalipare-Malang, Oro-oro Pule-Kejayan Pasuruan, Kedung Pengaron-Pasuruan and Jorongan-Leces Probolinggo. The materials used in this research are the eleven result numbers of physic nut hybrids, they are SP38XHS49, SP8XHS49, SP8XSP16, SP8XSP38, SP33XHS49, SM35XHS49, SM35XSP38, IP1AXHS49, IP1AXSP38, IP1PXHS 49, IP1PXSP38, and their parental, they are HS49, SP16, SP38, SP8, SP33, SM35, IP1A, IP1P, IP3P. Observation was done during the plants’ generative phase, on the second harvest. The results showed that SP38XHS49 hybrid on Kedung Pengaron, produces the highest seeds dry weight per hectare (1170 kg/ha) with 62.33 gram of dry weight of 100 seeds and the oil content is 32.56%. The highest average of dry seed productions from all planting sites achieved on the crossing between SP38XHS49 (658.75 kg/hectare) and followed by SP8XHS49 (607.5 kg/hectare). If the comparison of the four locations, the highest average productivity of physic nut achieved on location Jorongan, Leces, Probolinggo. In general, the data proves that the hybrid result from the crossing shows the higher production level compare to their parental. The dry weight of 100 seeds produced ranged from 54.03 grams to 68.29 grams. Of all four planting sites, it shows that the highest 100 seeds dry weight achieved by the crossing between IP1P-XHS49 which is 64.63 grams. The seed oil content ranged from 27.04 to 35.24 percent. The highest average of seed oil content achieved by the crossing between SM35XSP38 (32.035%). 展开更多
关键词 PHYSIC Nut JATROPHA curcas Linn. HYBRIDS Dry lands Second HARVEST
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Modelling the Potential Distribution of <i>Vitellaria paradoxa</i>subsp. <i>nilotica</i>(C.F. Gaertn) across the Kidepo Landscape of Uganda in the Face of Climate Change
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作者 Isaac Tom Okurut John Bosco Lamoris Okullo +1 位作者 Daniel Waiswa Julius Muyizzi 《Journal of Geoscience and Environment Protection》 2020年第8期14-24,共11页
Climate change and human activities are increasingly linked with the extinction of species globally. In semi-arid regions, these pressures threaten the natural distribution and ecology of species. The threat that the ... Climate change and human activities are increasingly linked with the extinction of species globally. In semi-arid regions, these pressures threaten the natural distribution and ecology of species. The threat that the shea butter tree (<em>Vitellaria paradoxa</em> subsp. <em>nilotica</em>) faces from human activity is well researched yet the sensitivity of its distribution to climate change remains barely known. We set out to assess the potential distribution of <em>Vitellaria</em> under different climate change scenarios using a MaxEnt. A current distribution model was first developed using only biophysical variables of soil type, temperature, precipitation, land use type, and elevation. This model was then projected onto two global warming scenarios (RCP 4.5 & RCP 8.5) for 2050 and 2070 using multi-model averages (BCC-CSM, CSM4, and MIROC5) derived from three general circulation models. Reductions are seen in distribution area across the landscape with soil type being the most important variable. These results draw useful implications for conservation of <em>Vitellaria</em> in that they show how it is vulnerable is to a changing climate as its natural range is mostly reduced. Since climate change is important in the distribution of the shea butter tree, the areas with highest suitability in this study can be used in establishing the Shea butter tree sustainable use zones/area within the Kidepo Critical Landscape (KCL), Uganda. 展开更多
关键词 Mapping Biophysical Variables General Circulation Models Dry land MAXENT
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Estimating Ecological Characteristics and Carbon Stock in Uneven-Aged Plantations of Acacia senegal L. in the Savannah Woodlands of Sudan
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作者 Fatima Elhassan Awadalla Abass Safa Salaheldine Mubarak Khugali +4 位作者 Nagla Abdelmounaim Mohammed Ahmed Ahmed Laamrani Elsadig Agabna Elhadi Ahmed Ali Hassabelkareem Siddig Edouard Konan Kouassi 《Journal of Environmental Protection》 CAS 2023年第5期404-418,共15页
The aim of this study was to assess Acacia senegal trees’ characteristics as well as evaluate the carbon stock under a variety of ages in the El Demokeya forest in Sudan, where the Gum Arabic belt is located. 12 samp... The aim of this study was to assess Acacia senegal trees’ characteristics as well as evaluate the carbon stock under a variety of ages in the El Demokeya forest in Sudan, where the Gum Arabic belt is located. 12 sample plots, in 2021 were randomly distributed to represent the entire area of the forest prior to the required measurements. The sample was designed as squire plots with one hectare. In each sample plot, all trees were counted, their height (m), and Diameters Breast Height (DBH in cm), respectively. The results showed the highest number of trees per ha at age 20 years old and the lowest number at age 47 years, while the highest values of DBH and volume were found at age 47 years old. As a result, the maximum and minimum values of the aboveground biomass were found in the age 47 years old and 16 years, accounting for 19.87 tons and 1.9 tons respectively. Thus, the amount of carbon stock was 11.92 tons/ha in the 35-years-old and 1.19 tons/ha in the 21-year stands. Furthermore, the average carbon stock in all plots was estimated as 18.70 tons/ha and hence the total carbon stock in the El Demokeya forest is equal to 620.11 tons. Conclusively, the characteristics of trees, amount of aboveground biomass and carbon stock in the El Demokeya forest varied among the uneven-aged plantation groups. The study recommends and encourages the protection of A. senegal in order to increase the carbon sink as well as protect the environment in the era of climatic changes. 展开更多
关键词 Aboveground Biomass Soil Organic Carbon Dry lands Forest Climate Change Mitigation Carbon
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Dryland Pastoralism Climate Landscape and Food Security in the Suam River Basin of Kenya
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作者 Namenya Daniel Naburi Edward M. Mugalavai +2 位作者 Kaleb Mwendwa Gilbert Ouma Clinton Ouma 《American Journal of Climate Change》 2022年第3期173-196,共24页
River basins in the drylands of Sub-Saharan Africa have traditionally been utilized for pastoral livelihoods under communal land tenure. Communities in West Pokot in Kenya have continued to experience increased precip... River basins in the drylands of Sub-Saharan Africa have traditionally been utilized for pastoral livelihoods under communal land tenure. Communities in West Pokot in Kenya have continued to experience increased precipitation and temperature as a result of climate variability and change. This study aimed at assessing the impact of climate variability and change at micro-basin level in order to address research and policy gaps on climate change and food security as policy arena shifts from centralized to decentralized governance in Kenya. Primary quantitative data was collected from 387 households’ perceptions of climate variability and change and its implications on food security were measured. Food security index score was calculated. The annual rainfall trend over Suam river basin for the period (1981-2020), was characterized by a linearly increasing annual rainfall trend. Mann Kendall test Z-statistics and Tau were at 2.3578 and 0.0720 respectively. The basin experienced the highest rainfall variability during the first decade (1981-1990) with the highest coefficient of rainfall variation noted at 11.5%. The highest temperature was recorded in the third decade (2001-2010) and fourth decade (2011-2020) at 27.0 and 28.2 degrees Celsius respectively. However, the overall index score for food security was 55.78 with food availability scoring the highest index, mean (SD) of 63.41 (36.52). This was attributed to households’ practice of both nomadic pastoralism and agro-pastoralism activities. Climate variability and change, have resulted in increased amount of rainfall received providing for opportunity investment in rain water harvesting to support both pastoralism and agro-pastoralism production to enhance food security. 展开更多
关键词 Climate Variability and Change Dry land Food Security Pastoralism Suam River Basin
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不同耕作方式与有机肥施用对旱地麦田土壤磷组分的影响
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作者 张鹏飞 杨娜 +4 位作者 王珂 杨志国 王慧 王晓民 张建诚 《中国生态农业学报(中英文)》 CAS CSCD 北大核心 2024年第10期1701-1708,共8页
为探讨耕作措施和有机肥施用对旱地麦田土壤磷组分的影响,本研究依托2007年布设的黄土高原旱地小麦耕作与施肥长期定位试验,采用Tiessen磷素分级方法,系统研究了深翻+化肥(T)、深翻+鸡粪+化肥(TM)、免耕+化肥(NT)和免耕+鸡粪+化肥(NTM) ... 为探讨耕作措施和有机肥施用对旱地麦田土壤磷组分的影响,本研究依托2007年布设的黄土高原旱地小麦耕作与施肥长期定位试验,采用Tiessen磷素分级方法,系统研究了深翻+化肥(T)、深翻+鸡粪+化肥(TM)、免耕+化肥(NT)和免耕+鸡粪+化肥(NTM) 4种农艺措施下麦田0~20 cm土层有效磷、全磷和磷组分分布特征。结果表明:1) NT处理有效磷含量较T处理提高58.37%,有机肥处理(NTM和TM)有效磷和全磷含量均显著高于不施有机肥处理(NT和T),NTM处理的有效磷和全磷含量较TM处理分别显著提高11.43%和43.41%。2)与T处理相比,NT、NTM和TM处理可不同程度提高0~20 cm土层活性无机磷组分NaHCO_(3)-Pi以及中活性无机磷组分NaOH-Pi含量,尤其以NTM和TM处理效果最好。3) NT处理的NaHCO_(3)-Po和NaOH-Po较T处理分别显著提高53.07%和55.56%,NTM处理的这2种组分含量较TM处理分别显著提高90.84%和60.31%,Residual-P NT处理较T以及NTM处理较TM分别提高12.90%和36.60%。4)长期定位试验地每年施入的磷肥在土壤中有盈余,残留的磷主要以NaHCO_(3)-Pi、D.HCl-Pi、NaHCO_(3)-Po和C.HCl-Po形态存在,免耕增施有机肥促进了稳定性磷(C.HClPo)向活性磷(NaHCO_(3)-P)和潜在活性磷(NaOH-P)的转化;偏最小二乘(PLS)回归分析结果表明,NaHCO_(3)-Pi和NaOH-Pi是最有效的磷源,对小麦产量的提升贡献较大,NTM处理对这2种磷组分积累的促进效果最明显。综上免耕增施有机肥是发展黄土高原旱作农业值得推广的农艺措施,同时在推广应用时需要考虑减少化学磷肥用量。 展开更多
关键词 免耕 有机肥 土壤磷组分 土壤有效磷 全磷 黄土高原旱地
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中国西南地区旱坡地碳减排研究进展与展望
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作者 王谢 杨琴 +7 位作者 刘禹池 李芹 杨勤 陈冠陶 岳丽杰 张建华 陈新平 刘永红 《作物学报》 CAS CSCD 北大核心 2024年第7期1635-1646,共12页
农田生态系统既是碳源,又是碳汇,具备很强的减排固碳潜力,对全球碳循环贡献巨大。西南地区旱坡地长期小规模、碎片化的农业生产方式给区域碳排放带来极大的不确定性。探索西南旱坡地的碳排放特征和减排途径对于改善环境、提升区域农业... 农田生态系统既是碳源,又是碳汇,具备很强的减排固碳潜力,对全球碳循环贡献巨大。西南地区旱坡地长期小规模、碎片化的农业生产方式给区域碳排放带来极大的不确定性。探索西南旱坡地的碳排放特征和减排途径对于改善环境、提升区域农业生产潜力具有重要意义。本研究系统总结了我国西南地区旱坡地农田生态系统主要温室气体(CO_(2)、N_(2)O)的产生环节,探讨了旱坡地固碳减排新材料与新技术的应用效果,提出了未来西南地区旱坡地的固碳减排策略。(1)鉴于西南地区旱坡地的区域资源禀赋、产业基础、生产规模、经营方式、生态功能等差异巨大,应结合地区特殊的农业生产条件,集成研发适宜的固碳减排措施和监测体系,探索全球变暖背景下西南旱坡地碳排放过程及其内在机制,以全面提升地区农业生产应对气候变化的韧性。(2)鉴于西南地区农作物复种指数较高且作物空间分布斑块化,应依据国家战略和地方规划,以绿色高产优质为目标导向,改进农业生产方式,优化产业空间布局。(3)由于西南地区旱坡地碳减排是一个复合过程,亟需根据今后较长一段时间内区域农业生产的实际结构和功能需求,有针对性地对各项成熟的减排技术、固碳产品和固碳模式进行优化组合,形成综合性的固碳减排方案。综上,本综述期望为进一步研究西南地区旱坡地农田生态系统的碳源和碳汇特征,以及合理调整农田管理措施提供全面的有效参考。 展开更多
关键词 温室气体 旱坡地 固碳减排 中国西南地区
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辣椒漂盘苗机械化移栽适应性研究
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作者 吴雪梅 管宜萱 +1 位作者 耿广东 张大斌 《农机化研究》 北大核心 2024年第8期179-185,共7页
为了探索辣椒漂盘苗对机械化移栽的适应性,以贵州某辣椒基地所育适栽期辣椒漂盘苗和2ZB-2旱地吊杯鸭嘴式移栽机为测试对象,完成了辣椒苗形态特征参数测量、落苗基质损失及田间机械栽植的试验研究。结果表明:从辣椒苗的苗高、叶面展幅、... 为了探索辣椒漂盘苗对机械化移栽的适应性,以贵州某辣椒基地所育适栽期辣椒漂盘苗和2ZB-2旱地吊杯鸭嘴式移栽机为测试对象,完成了辣椒苗形态特征参数测量、落苗基质损失及田间机械栽植的试验研究。结果表明:从辣椒苗的苗高、叶面展幅、基质情况来看,所育漂盘苗基质饱满,且适于膜上移栽常用的鸭嘴式栽植器;漂盘苗基质含水率在56.4%~63.5%时,利于机械移栽的基质保持;田间机械移栽的栽植深度合格率、漏栽率、伤苗率分别为76.7%、2.4%、3.2%,满足指标要求;直立度合格率为88.7%,低于93%的指标下限。总体来说,辣椒漂盘苗与移栽机适应性较好,基本能达到贵州辣椒机械化栽植作业要求。 展开更多
关键词 辣椒 漂浮育苗 机械化移栽 旱地移栽机 栽植性能
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陇东旱地冬小麦品种抗旱性鉴定
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作者 杨虓 刘自成 夏先春 《寒旱农业科学》 2024年第6期522-526,共5页
为研究陇东特殊干旱气候条件下抗旱育种的进展与现状,选取近20 a陇东旱地选育的14个冬小麦新品种(系)为材料,以籽粒产量抗旱指数等为全生育期抗旱性鉴定指标,在旱棚进行全生育期干旱胁迫试验。结果表明,陇育4号和宁麦5号抗旱指数在1.100... 为研究陇东特殊干旱气候条件下抗旱育种的进展与现状,选取近20 a陇东旱地选育的14个冬小麦新品种(系)为材料,以籽粒产量抗旱指数等为全生育期抗旱性鉴定指标,在旱棚进行全生育期干旱胁迫试验。结果表明,陇育4号和宁麦5号抗旱指数在1.100~1.299范围内,抗旱级别为2级;陇育7号和陇鉴387抗旱指数在0.700~0.899范围内,抗旱级别为4级;其余10个材料抗旱指数在0.900~1.099范围内,抗旱级别为3级。抗旱性级别在2~3级的材料占85.7%。产量性状主因子分析发现,抗旱级别为2级的陇育4号和宁麦5号,在干旱胁迫下有效穗数、穗粒数和千粒重无明显变化;抗旱级别为4级的陇育7号和陇鉴387,在干旱胁迫下有效穗数、穗粒数和千粒重均减幅较大;抗旱级别为3级的其余10个材料在干旱条件下,其产量性状三要素有效穗数、穗粒数、千粒重中只有一项发生变化,没有两项叠加变化。 展开更多
关键词 陇东旱地 冬小麦 抗旱性 抗旱指数 产量因子
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湄公河典型区域旱雨季土地利用及土壤侵蚀差异研究
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作者 赵娜 张道熙 +4 位作者 韩东枫 陈小娟 邱娟 金瑶 龚昱田 《水生态学杂志》 CSCD 北大核心 2024年第2期47-53,共7页
以湄公河干流老挝沙湾拿吉至柬埔寨桔井段重要支流南蒙河、色丹河、色贡河、色桑河、斯雷博河及其左右岸缓冲区50 km范围为研究区域,基于Landsat8遥感和河网数据,对比植被覆盖度以及空间分布特征,分析区域内旱季(1-2月)、雨季(6-9月)土... 以湄公河干流老挝沙湾拿吉至柬埔寨桔井段重要支流南蒙河、色丹河、色贡河、色桑河、斯雷博河及其左右岸缓冲区50 km范围为研究区域,基于Landsat8遥感和河网数据,对比植被覆盖度以及空间分布特征,分析区域内旱季(1-2月)、雨季(6-9月)土地利用及土壤侵蚀变化。结果表明,季节性降雨导致土地利用变化明显,旱、雨季土地利用变化主要表现为河道沿岸水体动态变化;旱季水体面积较雨季净减少43 259 hm^(2),占总变化面积的93.8%;雨季至旱季耕地转化占总变化面积38.00%(17 514.44 hm^(2)),其次为灌木地(22.98%,10 590.54 hm^(2))和裸地(21.77%,10 033.32 hm^(2))。土地利用类型转化导致土壤侵蚀变化,旱、雨季土壤极强烈侵蚀和剧烈侵蚀区域变化不大;旱季以轻度侵蚀、中度侵蚀增加为主,净增加面积分别为4 107 hm^(2)和5 864 hm^(2),分别占总变化面积的36.9%和52.7%;增加面积主要由无侵蚀类型发展而来,体现在旱季沿岸水体面积的大幅降低。建议在水土保持过程中,改传统稻田种植为耕作、轮作和培肥一体化的水保措施,增强基础设施建设,加强河岸带生态护坡建设与管理,降低自然洪水或人为工程对自然林地和植被的破坏。 展开更多
关键词 土地利用 土壤侵蚀 旱雨季 湄公河
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