This research was aimed to evaluate the productivity of native pasture in Timor Island by introducing various palatable species.The study was carried out on native pasture in Tuatuka,Timor Island for seven months.The ...This research was aimed to evaluate the productivity of native pasture in Timor Island by introducing various palatable species.The study was carried out on native pasture in Tuatuka,Timor Island for seven months.The study was performed by using randomized block design(RBD)with eight treatments(S0:no introduction,S1:Cynodon dactilon,S2:Dicanthium aristatum,S3:C.plectotachyus,S4:Brachiaria decumbens,S5:Desmanthus virgatus,S6:Macroptilium atropurpureum,S7:Clitoria ternatea)with four replications.Procedures on this study include trial plots preparation,tillers preparation for each species,introduction of species in trial plots,maintenance and observation of the productivity.Variables observed were forage production(fresh and dry matter(DM)in ton/ha),nutrient content(%)and stock capacity(animal unit(AU)/ha).Data were analyzed for variance based on RBD and followed by Duncan’s test.Analysis of variance showed that introduction of species had a very significant effect(p<0.01)on all observed variables.The introduction of M.atropurpureum produced the highest fresh forage(2.1 t/ha)and DM production(0.69 t/ha).M.atropurpureum also had the highest DM content(43.61%),nitrogen free extract(52.52%)and stock capacity(1.06 AU/ha).The highest crude protein and crude fiber content were found in D.virgatus(4.31%and 36.62%).The highest extract ether was observed in D.aristatum(1.48%).No introduction had the lowest productivity,but demonstrated the highest ash content.The introduction of palatable species increased the productivity of native pasture in Timor and M.atropupureum was the best introduced species.展开更多
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
Central Asian dry lands are grass- and desert shrub-dominated ecosystems stretching across Northern Eurasia. This region supports a population of more than 1 00 million which continues to grow at an average rate of 1....Central Asian dry lands are grass- and desert shrub-dominated ecosystems stretching across Northern Eurasia. This region supports a population of more than 1 00 million which continues to grow at an average rate of 1.5% annually. Dry steppes are the primary grain and cattle growing zone within Central Asia. Degradation of this ecosystem through burning and overgrazing directly impacts economic growth and food supply in the region. Fire is a recurrent disturbance agent in dry lands contributing to soil erosion and air pollution. Here we provide an overview of inter-annual and seasonal fire dynamics in Central Asia obtained from remotely sensed data. We evaluate the accuracy of the Moderate Resolution Imaging Spectroradiometer (MODIS) global fire products within Central Asian dry lands and use these products to characterize fire occurrence between 2001 and 2009. The results show that on average -15 million ha of land burns annually across Central Asia with the majority of the area burned in August and September in grasslands. Fire is used as a common crop residue management practice across the region. Nearly 89% of all burning occurs in Kazakhstan, where 5% and 3% of croplands and grasslands, respec- tively, are burned annually.展开更多
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
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
An earlier baseline study (Jellason et al. in preparation) has identified some of the key challenges faced by farmers and from that, appropriate Good Agricultural Practices (GAPs) have been selected for the enviro...An earlier baseline study (Jellason et al. in preparation) has identified some of the key challenges faced by farmers and from that, appropriate Good Agricultural Practices (GAPs) have been selected for the environment the farmers find themselves in and based on a review of available literature. Farmer action plans for enhancing smallholder resilience, GHGs emission mitigation and food security for these dry lands were developed. Expert opinions on the applicability of the selected GAPs to inform farmer co-learning and to validate the suitability of these practices in a dry land context were sought through the Delphi study. Experts were also invited to offer suggestions for improvement of the training action plan. Two rounds of a modified Delphi survey were carried out with experts from diverse backgrounds and locations across the globe to solicit their opinion. Results show that experts' agreement was reached on most of the action plan items. The results and opinions obtained from the survey were reviewed and adapted into the action plan leading to the development of GAPs for the co-learning exercise.展开更多
A long-term fertilizer experiment on dry land of the Loess Plateau, northwestChina, has been conducted since 1984 to study the distribution and accumulation of NO_3-N down to adepth of 400 cm in the profile of a coars...A long-term fertilizer experiment on dry land of the Loess Plateau, northwestChina, has been conducted since 1984 to study the distribution and accumulation of NO_3-N down to adepth of 400 cm in the profile of a coarse-textured dark loessial soilafter continuous winter wheatcropping. Thirteen fertilizer treatments consisted of four levels of N and P applied alone or incombination. Annual N and P (P_2O_5) rates were 0, 45, 90, 135 and 180 kg ha^(-1). After 15successive cropping cycles, the soil samples were taken from each treatment for analysis of NO_3-Nconcentration. The results showed that NO_3-N distribution in the soil profile was quite differentamong the treatments. The application of fertilizer N alone resulted in higher NO_3-N concentrationin the soil profile than the combined application of N and P, showing that application of P couldgreatly reduce the NO_3-N accumulation. With an annual application of 180 kg N ha^(-1) alone, a peakin NO_3-N accumulation occurred at 140 cm soildepth, and the maximum NO_3-N concentration in thesoils was 67.92 mg kg^(-1). The amount of NO_3-N accumulated in the soil profile decreased as thecumulative N uptake by the winter wheat increased. Application of a large amount of N resulted inlowerN recoveries in winter wheat and greater NO_3-N accumulation in soil profile. KO_3-N did notenter underground water in the study region; therefore, there is no danger of underground waterpollution. Amount of NO_3-N accumulation can be predicted by an equation according to annual N and Prates based on the results of this experiment.展开更多
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
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
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
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
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
In order to evaluate the effect of subsoiling on the soil physical properties and wheat yield in dry land conditions, this research was conducted in Mamassani area of Fars province in Iran. The experiment was laid dow...In order to evaluate the effect of subsoiling on the soil physical properties and wheat yield in dry land conditions, this research was conducted in Mamassani area of Fars province in Iran. The experiment was laid down in the form of a complete block experimental design with four treatments and four replications for three years. Treatments included: (1) conventional tillage without using subsoiler which was control treatment (So); (2) using subsoiler with the shank space of 40 cm which was equal to the subsoiling depth (SO; (3) using subsoiler with the shank space of 60 cm which was 1.5 times of the subsoiling depth (S2); and (4) using subsoiler with the shank space of 80 cm which was 2 times of the subsoiling depth (S3). Subsoiling depth was set at 40 cm which was the lower limit of the hard pan depth in the soil. Soil cone index, soil bulk density, soil moisture content, wheat yield, and yield components were measured in this study and SAS software was used to analyze the collected data. Results showed that subsoiling decreased the soil bulk density and cone index, and increased water retention of the soil. Results also revealed that applying subsoiler increased wheat yield and yield components in our dry land conditions. Since subsoiling improved soil physical conditions and increases wheat yield, applying subsoiler in such a dry land conditions is therefore recommended. Results of this study also showed that subsoiling with the shank space of 40 cm and 60 cm had better performance compared to the shank space of 80 cm. On the other hand, shank space of 40 cm reduced the subsoiler effective working width and consequently effective field capacity. Therefore, subsoiler with a shank space of 60 cm is recommended for application in dry land soils of our type.展开更多
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
[Objectives]To evaluate the status of soil nutrient and fertility in main dry farming regions of Laos,and to explore differences in soil nutrient content between regions and crop types.[Methods]By collecting 57 soil s...[Objectives]To evaluate the status of soil nutrient and fertility in main dry farming regions of Laos,and to explore differences in soil nutrient content between regions and crop types.[Methods]By collecting 57 soil samples in the 0-20 cm layer of the main dryland in southern and northern provinces of Laos.Soil pH,organic matter,total nitrogen,available nitrogen,available phosphorus,available potassium,exchangeable calcium,exchangeable magnesium and available zinc content were analyzed.[Results]The soil in the main dry farming regions of Laos was acidic,the overall fertility level was good,and the exchangeable calcium and magnesium contents were low.There were differences in soil nutrient content in the dry farming regions of southern and northern Laos.Drylands where cassava and maize were growed had higher fertility.[Conclusions]It is suggested to apply lime or alkaline fertilizer in the dry land with acid soil to increase soil pH and increase the supply of soil calcium and magnesium.Organic fertilizer should be applied to improve soil water retention capacity,and it is necessary to pay attention to the fertilization ratio of macroelements to balance fertilization.展开更多
The paper describes the capabilities and opportunities of Remote Sensing and GIS technologies for monitoring the rangeland vegetation and its dynamics under different type of factors. Potential of satellite data of La...The paper describes the capabilities and opportunities of Remote Sensing and GIS technologies for monitoring the rangeland vegetation and its dynamics under different type of factors. Potential of satellite data of Landsat 7 Enhanced Thematic Mapper Plus (ETM+) Imagery for monitoring the rangeland condition of Karnabchul semi desert was exemined. The paper presents the first stage of a method for vegetation assessment of rangelands based on spectral vegetation indices such as Normalized Difference Vegetation Index (NDVI) derived from remotely sensed data. Initial results of the research showed the Landsat satellite images can provide relevant information about current condition of rangeland vegetation. It is recommended to conduct further studies using remotely sensed data for improvement of the rangeland monitoring methods.展开更多
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
Rice precision hill-drop drilling technique in dry land uses fixed hill spacing to achieve orderly planting of crops and to attain good ventilating and day-lighting effects in rice fields.The technique is also benefic...Rice precision hill-drop drilling technique in dry land uses fixed hill spacing to achieve orderly planting of crops and to attain good ventilating and day-lighting effects in rice fields.The technique is also beneficial in improving root growth and root structure and in increasing lodging resistance.The high-yield record of Xinjiang Production and Construction Corp’s first division for three consecutive years shows that rice precision hill-drop drilling technique in dry land is one of the important directions to developed rice cultivating mechanization technology.To further improve the quality of rice precision hill-drop drilling machine for dry land,a single profiling,electro-hydraulic proportional real-time adjustment of system was developed according to the agronomic requirements.This machine can simultaneously finish various kinds of seedbed leveling,furrowing and seeding operations,as well as soil covering and pressing.Electro-hydraulic proportional speed regulation makes an AMESim simulation test and analyzes the stability and error of hydraulic adjusting planting distance.Bench testing was carried out on the metering device by simultaneously employing high speed photography technology and analyzing the relationship of the high speed of hill distance and seed charge height.Finally,machine trial was completed.The two-year field experiments of Xinjiang Production and Construction Corp showed that when the machine operation speed is 2.8-3.2 km/h,the sowing depth percent of pass is 75%or higher,the qualified rate of row spacing is 80%or more,the pass rate of row spacing is 90%or higher,and the quantity per hill is 75%or higher.This machine met the various indicators of hill sowing quality requirements.展开更多
China is making all-out efforts to fight severe drought China still faced the grim task of fighting a drought despite recent snowfalls and enhanced irrigation in major wheat growing regions,the country’s
文摘This research was aimed to evaluate the productivity of native pasture in Timor Island by introducing various palatable species.The study was carried out on native pasture in Tuatuka,Timor Island for seven months.The study was performed by using randomized block design(RBD)with eight treatments(S0:no introduction,S1:Cynodon dactilon,S2:Dicanthium aristatum,S3:C.plectotachyus,S4:Brachiaria decumbens,S5:Desmanthus virgatus,S6:Macroptilium atropurpureum,S7:Clitoria ternatea)with four replications.Procedures on this study include trial plots preparation,tillers preparation for each species,introduction of species in trial plots,maintenance and observation of the productivity.Variables observed were forage production(fresh and dry matter(DM)in ton/ha),nutrient content(%)and stock capacity(animal unit(AU)/ha).Data were analyzed for variance based on RBD and followed by Duncan’s test.Analysis of variance showed that introduction of species had a very significant effect(p<0.01)on all observed variables.The introduction of M.atropurpureum produced the highest fresh forage(2.1 t/ha)and DM production(0.69 t/ha).M.atropurpureum also had the highest DM content(43.61%),nitrogen free extract(52.52%)and stock capacity(1.06 AU/ha).The highest crude protein and crude fiber content were found in D.virgatus(4.31%and 36.62%).The highest extract ether was observed in D.aristatum(1.48%).No introduction had the lowest productivity,but demonstrated the highest ash content.The introduction of palatable species increased the productivity of native pasture in Timor and M.atropupureum was the best introduced species.
文摘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.
文摘Central Asian dry lands are grass- and desert shrub-dominated ecosystems stretching across Northern Eurasia. This region supports a population of more than 1 00 million which continues to grow at an average rate of 1.5% annually. Dry steppes are the primary grain and cattle growing zone within Central Asia. Degradation of this ecosystem through burning and overgrazing directly impacts economic growth and food supply in the region. Fire is a recurrent disturbance agent in dry lands contributing to soil erosion and air pollution. Here we provide an overview of inter-annual and seasonal fire dynamics in Central Asia obtained from remotely sensed data. We evaluate the accuracy of the Moderate Resolution Imaging Spectroradiometer (MODIS) global fire products within Central Asian dry lands and use these products to characterize fire occurrence between 2001 and 2009. The results show that on average -15 million ha of land burns annually across Central Asia with the majority of the area burned in August and September in grasslands. Fire is used as a common crop residue management practice across the region. Nearly 89% of all burning occurs in Kazakhstan, where 5% and 3% of croplands and grasslands, respec- tively, are burned annually.
文摘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.
文摘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.
文摘An earlier baseline study (Jellason et al. in preparation) has identified some of the key challenges faced by farmers and from that, appropriate Good Agricultural Practices (GAPs) have been selected for the environment the farmers find themselves in and based on a review of available literature. Farmer action plans for enhancing smallholder resilience, GHGs emission mitigation and food security for these dry lands were developed. Expert opinions on the applicability of the selected GAPs to inform farmer co-learning and to validate the suitability of these practices in a dry land context were sought through the Delphi study. Experts were also invited to offer suggestions for improvement of the training action plan. Two rounds of a modified Delphi survey were carried out with experts from diverse backgrounds and locations across the globe to solicit their opinion. Results show that experts' agreement was reached on most of the action plan items. The results and opinions obtained from the survey were reviewed and adapted into the action plan leading to the development of GAPs for the co-learning exercise.
基金Project supported by the Chinese Academy of Sciences (No. KZCX2)the National Natural Science Foundation of China (No. 40025106).
文摘A long-term fertilizer experiment on dry land of the Loess Plateau, northwestChina, has been conducted since 1984 to study the distribution and accumulation of NO_3-N down to adepth of 400 cm in the profile of a coarse-textured dark loessial soilafter continuous winter wheatcropping. Thirteen fertilizer treatments consisted of four levels of N and P applied alone or incombination. Annual N and P (P_2O_5) rates were 0, 45, 90, 135 and 180 kg ha^(-1). After 15successive cropping cycles, the soil samples were taken from each treatment for analysis of NO_3-Nconcentration. The results showed that NO_3-N distribution in the soil profile was quite differentamong the treatments. The application of fertilizer N alone resulted in higher NO_3-N concentrationin the soil profile than the combined application of N and P, showing that application of P couldgreatly reduce the NO_3-N accumulation. With an annual application of 180 kg N ha^(-1) alone, a peakin NO_3-N accumulation occurred at 140 cm soildepth, and the maximum NO_3-N concentration in thesoils was 67.92 mg kg^(-1). The amount of NO_3-N accumulated in the soil profile decreased as thecumulative N uptake by the winter wheat increased. Application of a large amount of N resulted inlowerN recoveries in winter wheat and greater NO_3-N accumulation in soil profile. KO_3-N did notenter underground water in the study region; therefore, there is no danger of underground waterpollution. Amount of NO_3-N accumulation can be predicted by an equation according to annual N and Prates based on the results of this experiment.
基金supported by the Major State Basic Research Development Program of People’s Republic of China(G1999011708).
文摘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-
基金supported as a special project by the Agriculture Ministry of China(Grant No.201503119)the Natural Science Foundation of China(Grant No.41471232)
文摘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.
文摘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.
基金Supported by National Research Initiative of the USDA Cooperative State Research, Education and Extension Service (2004-35504-14808)
文摘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.
基金Key Technology Research for Development and Efficient Cultivation and Utilization of Forage Mulberry(2013SZ03)
文摘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.
文摘In order to evaluate the effect of subsoiling on the soil physical properties and wheat yield in dry land conditions, this research was conducted in Mamassani area of Fars province in Iran. The experiment was laid down in the form of a complete block experimental design with four treatments and four replications for three years. Treatments included: (1) conventional tillage without using subsoiler which was control treatment (So); (2) using subsoiler with the shank space of 40 cm which was equal to the subsoiling depth (SO; (3) using subsoiler with the shank space of 60 cm which was 1.5 times of the subsoiling depth (S2); and (4) using subsoiler with the shank space of 80 cm which was 2 times of the subsoiling depth (S3). Subsoiling depth was set at 40 cm which was the lower limit of the hard pan depth in the soil. Soil cone index, soil bulk density, soil moisture content, wheat yield, and yield components were measured in this study and SAS software was used to analyze the collected data. Results showed that subsoiling decreased the soil bulk density and cone index, and increased water retention of the soil. Results also revealed that applying subsoiler increased wheat yield and yield components in our dry land conditions. Since subsoiling improved soil physical conditions and increases wheat yield, applying subsoiler in such a dry land conditions is therefore recommended. Results of this study also showed that subsoiling with the shank space of 40 cm and 60 cm had better performance compared to the shank space of 80 cm. On the other hand, shank space of 40 cm reduced the subsoiler effective working width and consequently effective field capacity. Therefore, subsoiler with a shank space of 60 cm is recommended for application in dry land soils of our type.
文摘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.
基金Guangxi Science and Technology Plan Project(Gui Ke AD17195026&Gui Ke AD19259007)Science and Technology Development Fund Project of Guangxi Academy of Agricultural Sciences(Gui Nong Ke 2016ZX11)Fund Project of Guangxi Academy of Agricultural Sciences(2019ZX121).
文摘[Objectives]To evaluate the status of soil nutrient and fertility in main dry farming regions of Laos,and to explore differences in soil nutrient content between regions and crop types.[Methods]By collecting 57 soil samples in the 0-20 cm layer of the main dryland in southern and northern provinces of Laos.Soil pH,organic matter,total nitrogen,available nitrogen,available phosphorus,available potassium,exchangeable calcium,exchangeable magnesium and available zinc content were analyzed.[Results]The soil in the main dry farming regions of Laos was acidic,the overall fertility level was good,and the exchangeable calcium and magnesium contents were low.There were differences in soil nutrient content in the dry farming regions of southern and northern Laos.Drylands where cassava and maize were growed had higher fertility.[Conclusions]It is suggested to apply lime or alkaline fertilizer in the dry land with acid soil to increase soil pH and increase the supply of soil calcium and magnesium.Organic fertilizer should be applied to improve soil water retention capacity,and it is necessary to pay attention to the fertilization ratio of macroelements to balance fertilization.
文摘The paper describes the capabilities and opportunities of Remote Sensing and GIS technologies for monitoring the rangeland vegetation and its dynamics under different type of factors. Potential of satellite data of Landsat 7 Enhanced Thematic Mapper Plus (ETM+) Imagery for monitoring the rangeland condition of Karnabchul semi desert was exemined. The paper presents the first stage of a method for vegetation assessment of rangelands based on spectral vegetation indices such as Normalized Difference Vegetation Index (NDVI) derived from remotely sensed data. Initial results of the research showed the Landsat satellite images can provide relevant information about current condition of rangeland vegetation. It is recommended to conduct further studies using remotely sensed data for improvement of the rangeland monitoring methods.
基金Supported by Global COE Program (Global Center of Excellence for Dryland Science) Funded by MEXT"Historical Interactions between the Multi-Cultural Societies and the Natural Environment in a Semi-Arid Region in Central Eurasia" Project Funded by Research Institute for Humanity and Nature, Japan
文摘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.
文摘Rice precision hill-drop drilling technique in dry land uses fixed hill spacing to achieve orderly planting of crops and to attain good ventilating and day-lighting effects in rice fields.The technique is also beneficial in improving root growth and root structure and in increasing lodging resistance.The high-yield record of Xinjiang Production and Construction Corp’s first division for three consecutive years shows that rice precision hill-drop drilling technique in dry land is one of the important directions to developed rice cultivating mechanization technology.To further improve the quality of rice precision hill-drop drilling machine for dry land,a single profiling,electro-hydraulic proportional real-time adjustment of system was developed according to the agronomic requirements.This machine can simultaneously finish various kinds of seedbed leveling,furrowing and seeding operations,as well as soil covering and pressing.Electro-hydraulic proportional speed regulation makes an AMESim simulation test and analyzes the stability and error of hydraulic adjusting planting distance.Bench testing was carried out on the metering device by simultaneously employing high speed photography technology and analyzing the relationship of the high speed of hill distance and seed charge height.Finally,machine trial was completed.The two-year field experiments of Xinjiang Production and Construction Corp showed that when the machine operation speed is 2.8-3.2 km/h,the sowing depth percent of pass is 75%or higher,the qualified rate of row spacing is 80%or more,the pass rate of row spacing is 90%or higher,and the quantity per hill is 75%or higher.This machine met the various indicators of hill sowing quality requirements.
文摘China is making all-out efforts to fight severe drought China still faced the grim task of fighting a drought despite recent snowfalls and enhanced irrigation in major wheat growing regions,the country’s