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Suitability evaluation and regionalization of maize planting in Hedong Area of Gansu Province

- , 2018, DOI: 10.7606/j.issn.1000-7601.2018.03.34
Abstract: 利用1951—2015年甘肃省河东地区17个典型测站气候资料,采用均值法并运用Origin8.0软件对其近65年来年平均气温、4—9月份玉米生育期平均降水量、≥10℃积温总量和年平均霜期日数的空间分布特征进行了分析,结合温度、霜期日数和生育期降水数据对不同测站玉米种植适宜性予以评价。通过对影响研究区玉米种植适宜性主要气候因子分析,并借助GIS空间分析技术得出河东地区玉米种植适宜性区划等级结果。结果表明:(1) 研究区玉米种植适宜性等级总体表征为东高西低。(2) 最适宜区范围最小,密集分布在平凉市和庆阳市南部区域,为正宁县、宁县、泾川县、灵台县、崇信县和庆阳市区。(3) 适宜区主要分布在陇东黄土高原大部、陇南秦巴山区(两当县除外)以及临夏回族自治州大部分地区。(4) 次适宜区集中分布在陇中黄土高原,另有零星分布如环县、两当县、和政县和康乐县。(5) 不适宜区主要分布在甘南高原。
Based on data from 17 typical weather stations from 1951 to 2015 in Hedong area of Gansu Province, spatial distribution characteristics of average temperature in the past 65 years, average precipitation of growth period of maize in 4~9 month, total amount of ≥10℃ accumulated temperature and the annual average number of frost free days were analyzed by using mean value method via Origin8.0 software.The suitability of maize planting in different stations was evaluated according to the temperature, the number of frost free days and precipitation data during growth period. Combining the analysis of the main climatic factors affecting the suitability of maize planting in the study area with GIS spatial analysis technology,maize planting suitability regionalization in Hedong area were obtained .The results showed following: (1) The overall characterization of the suitability of maize planting in the study area decreased from East to West. (2) The most suitable area was the smallest and densely distributed in the southern region of Pingliang city and Qingyang city, including Zhengning County, Ningxian County, Jingchuan County, Lingtai County, Chongxin County and Qingyang city. (3) The suitable areas were mainly distributed in the large part of Longdong Loess Plateau, Qin Ba mountain area in Longnan (except Liangdang County) and most of Linxia Hui Autonomous Prefecture. (4) The sub suitable areas were concentrated in the Loess Plateau of Longzhong, and sporadic distribution such as Huan County, Liangdang County, Hezheng County and Kangle County. (5) The unsuitable area was mainly distributed in the Gannan Plateau.
Suitability of Indigenous Maize Hybrids for Spring Planting in Pakistan  [PDF]
M. Hussain,S.R. Chughtai,H.I. Javed,H.N. Malik
Asian Journal of Plant Sciences , 2006,
Abstract: Maize, the leading world cereal, offers the greatest potential for increasing food productivity in countries like Pakistan. The average yield in Pakistan is low compared to the world average. An effective short term strategy to improve maize productivity is to replace the local low yielding varieties and landraces with high yielding hybrids. However, mainly due to very high cost of the imported hybrid seed in Pakistan, the hybrid technology has not been adopted on larger scales. Currently, 25% of the maize area is under hybrids in Pakistan. Therefore, there is a great need to develop, popularize and adopt maize hybrids with indigenous blood. Indigenous hybrids for agro-ecological zones not attended by the private multinational have been developed at National Agricultural Research Centre and tested in the respective ecologies. Six selected indigenous hybrids (NARC-2701, NARC-2702, NARC-2703, NARC-2704, NARC-2705, NARC-2707) were evaluated at two location during spring season. Four leading commercial hybrids (Bemisal-202, 3335, 2303 and 6525 from Engro, Pioneer, Rafhan and Monsanto) were used as checks for comparison. Some of the indigenously developed hybrids (NARC-2702, NARC-2703, NARC-2704, NARC- 2705) performed better than, or as good as their exotic counterparts. These hybrids exhibited desired idiotypes as indicated by plant and ear heights. The indigenous hybrids were earlier in maturity than the commercial checks. These results clearly indicate the superiority and suitability of locally developed (indigenous) maize hybrids for spring planting in Pakistan.
Shifting suitability for malaria vectors across Africa with warming climates
A Townsend Peterson
BMC Infectious Diseases , 2009, DOI: 10.1186/1471-2334-9-59
Abstract: I derive spatially explicit estimates of human populations living in regions newly suitable climatically for populations of two key Anopheles gambiae vector complex species in Africa over the coming 50 years, based on ecological niche model projections over two global climate models, two scenarios of climate change, and detailed spatial summaries of human population distributions.For both species, under all scenarios, given the changing spatial distribution of appropriate conditions and the current population distribution, the models predict a reduction of 11.3–30.2% in the percentage of the overall population living in areas climatically suitable for these vector species in coming decades, but reductions and increases are focused in different regions: malaria vector suitability is likely to decrease in West Africa, but increase in eastern and southern Africa.Climate change effects on African malaria vectors shift their distributional potential from west to east and south, which has implications for overall numbers of people exposed to these vector species. Although the total is reduced, malaria is likely to pose novel public health problems in areas where it has not previously been common.Malaria is a vector-borne anthroponosis, transmitted in large part by Anopheles mosquitoes, that endangers more than 2.5 × 109 humans annually [1]. Its transmission cycle has been modeled in great detail [2,3], but application of such process-based models has generally been limited to local and regional scales [4,5], given challenges in spatially explicit parameter estimation. An alternative approach that offers broadest applicability is that of focusing on vector species' geographic distributions via ecological niche modeling techniques now well tested [6-8] within frameworks for reconstructing the geographic dimensions of disease transmission [9].Implications of climate change for malaria transmission across Africa have been the subject of numerous commentaries [10-12] and a few
The research advances on the crop climate suitability influenced by global warming

ZHAO Feng,QAN Huai-Sui,
赵 峰

中国生态农业学报 , 2004,
Abstract: Some research methods and fundamental ideas of the global warming effects on the crop climate suitability in recent years in our country and abroad are introduced, and the conclusions of dynamic modeling and controlled experiments are stated. Finally,several critical research directions in the assessment and forecasting in the present climate impacts are put forward.
Responses of winter wheat growth to winter warming in Gansu Province

PU Jin-yong,YAO Yu-bi,MA Peng-li,DENG Zhen-yong,WANG Wei-tai,ZHANG Mou-cao,

应用生态学报 , 2007,
Abstract: Based on the observation data of the air temperature at Tianshui and Xifeng in 1951-2005 and of the phenology of winter wheat at Tianshui and Xifeng in 1981-2003, the tendency of winter warming in past 50 years and the responses of winter wheat growth to climate warming in Gansu Province were analyzed. The results showed that the growth and development of winter wheat were seriously influenced by winter warming. In recent 20 years or more, the overwintering mortality of winter wheat dropped to <2%, overwintering days reduced by 7-8 days, whole growth period shorted by 8-10 days, and jointing-flowering period extended by 7 days, which would benefit the production of winter wheat and the utilization of climatic resource. However, the higher winter temperature and lesser precipitation also made the grain yield instable and the plant diseases and insect pests more frequent, resulting in more uncertain factors in winter wheat safe production.
Evaluation of flue-cured tobacco planting suitability and crop rotation planning based on spatial information
基于空间信息的烤烟种植适宜性 评价与轮作规划

PENG Guang-xiong,HU De-yong,CHEN Feng-rui,GUO Ji-fa,CUI Wei-hong,

地理研究 , 2010,
Abstract: Digital precision agriculture has become a new trend for agricultural development in the world. The kernel technology of digital precision agriculture is spatial information technology. It is an important way to improve the capacity of sustainable development of flue-cured tobacco, using planting suitability evaluation and crop rotation planning based on spatial information technology. The land surface parameters used for conventional agricultural zoning and suitability evaluation are all based on the observation sites. Since the density of observation sites is very limited, it is difficult to obtain high-precision data in a large area. Therefore land surface parameters retrieved from remote sensing can be used to replace the parameters based on the observation sites. It can make the planting suitability evaluation and crop rotation planning more scientific and reasonable. Based on temperature, solar radiation and soil moisture obtained from remote sensing and DEM, with the support of topography, soil and land use factors derived from database, Suitability Evaluation Index (SEI) of flue-cured tobacco planting suitability in Luxi County is calculated at a 100 m×100 m grid size. The classification and spatial distribution of suitability evaluation results are then used to plan the crop rotation of flue-cured tobacco. Results show that the rate of crop rotation in Luxi County increased from 37.8% in 2002 to 63.7% in 2008, and there is still a wide gap to the goal rate of 95%. The planting utilization rate of most appropriate area is only about 28.1%, and there are about 2165 ha of most appropriate area for potential development. Therefore, in order to optimize the allocation of land resources, the planning of crop rotation should give first priority to flue-cured tobacco planting in most appropriate area. As remote sensing has reliable data support and has good ability to make up for the distortion of data caused by observation site loss, for planting suitability evaluation, remote sensing has more superiority than observation sites. Spatial information based crop rotation planning, verifying and supervising have good ability to improve the crop rotation rate of flue-cured tobacco and lay a foundation for sustainable development.
Impact of warming climate on crop water requirement in Gansu Province

WANG He-Ling,WANG Run-Yuan,ZHANG Qiang,NIU Jun-Yi,LU Xiao-Dong,

中国生态农业学报 , 2011,
Abstract: Global warming is an increasingly worrisome environmental and climatic phenomenon. Global average temperature increased by 0.60~0.70 oC over the last centuray, with an average temperature rise of 0.80~1.50 oC in China. Northwest China is one of the most sensitive areas to climate change. Temperature (a critical factor of global warming) is often used in an integrated method to calculate crop water demand. In other words, temperature afftects climate change, which in turn affects crop water needs. Crop water requirements in Northwest China is therefore critical in farm water cycle. It is also an important hydraulic and water-saving parameter in agricultural research, planning and design. This study addressed issues such as: the effect of climate change on agricultural water demand in different regions, and current lack of systematic and quantitative data to support crop water requirement research in the face of global warming. This study analyzed the effects of warming climate on crop water requirement in Gansu Province under different temperature scenarios (future temperature increases of 1~4 oC). The results showed that the effects of warming climate on crop water requirement were different for different crops. Warming climate greatly afftected water requirement of winter wheat, followed by spring wheat and maize. When future temperatures rose by 1~4 oC, water requirement of winter wheat increased by 3.05%~12.90%, which was the equivalent of 13.2~81.2 mm. That of maize increased by 2.49%~10.80%, the equivalent of 9.9~60.6 mm. Then spring wheat water requirement increased by 2.74%~11.69%, the equivalent of 6.7~40.0 mm. Regional differences were noted in the impact of warming climate on crop water requirement. The impact of warming climate on crop water requirement was highest for arid regions, followed by semi-arid regions, and then semi-humid regions. The least effect was for humid regions. When future temperatures rose by 1~4 oC, the temperature scenario caused additional irrigation water requirement of 1 243, 1 302, 1 374 and 1 465 million m3 for winter wheat; 794, 832, 878 and 930 million m3 for maize; and 497, 516, 542 and 576 million m3 for spring wheat, respectively. Warming climate worsened water shortage problems in the study area.
Affect of Climate Warming on Crops Planting Structure in Arid Zone of Northwestern China

LIU De-xiang,DONG An-xiang,LIANG Dong-sheng,NING Hui-fang,

中国沙漠 , 2007,
Abstract: Correlation analysis results show that the yearly mean temperature has significantly negative correlation with the cultivation area of winter wheat in Xinjiang and with the cultivation area of spring wheat in arid regions in northwestern China,but has significantly positive correlation with the cultivation area of corn in arid regions in northwestern China and the cultivation areas of cotton in Xinjiang Province and in Hexi corridor of Gsnsu Province.Climate warming and thermal resource increasing have resulted in the fast decreasing of spring and winter wheat planted areas,whereas the planted areas of thermophyte corn and cotton quickly extend.The planting structure of summer and autumn crops has apparently changed.
Potential Capacity of Cassava Planting in Guangxi: Assessment of Natural Suitability and Socio-Economic Restrictions

WANG Lu,YANG Hailong,FENG Zhiming,LV Yao,

资源科学 , 2012,
Abstract: Because of the fast consumption of fossil energy and associated environmental problems, governments have paid increasing attention to the development of the bio-energy industry. The Chinese government has formulated a series of policies to improve the bio-energy industry. In order to ensure the food security, the Chinese government has claimed that bio-ethanol could only be produced by non-food crops such as sweet sorghum and cassava. Cassava is a type of non-food crops and one of main materials of bio-ethanol production. With the increasing demands for cassava in Guangxi Zhuang Autonomous Region, which is the most important traditional cassava planting area, relevant institutions and government departments are paying increasing attention to the cultivation potential of cassava. In this paper, based on climate suitability, soil suitability, terrain suitability, and socio-economic restrictions of land use, we used the AHP method to evaluate the suitability of each index. Then, the suitability of comprehensive indexes was evaluated. At last, an assessment of its natural suitability and social restrictions of cassava planting in Guangxi was conducted, with its land production potential, potential capacity, and spatial distribution being quantitatively analyzed. Results show that among all indexes, the terrain condition was the leading limiting factor of cassava planting potential, followed by the soil condition. If the socio-economic restrictions of land use were not accounted for, 60% of the land area in Guangxi was suitable for cassava planting. On the contrary, the suitable land area would decrease to 1 155 ×103 ha. Compared with current plating area of 223 × 103 ha, there were up to 4 times cultivation potential. Concerning the spatial distribution, the key areas of cassava planting in the future are in the region of Liuzhou and Laibin. It is suggested that developing the bio-ethanol industry based on cassava in Guangxi would be a right choice, but the development speed should keep appropriate and the extensive mode of production has to be shifted to an intensive mode. Second, although the main areas of cassava planting are in Nanning, Wuzhou, and Guigang, the potential planting areas are Liuzhou and Laibin. Third, more emphasis should be placed on the environment and economy of cassava planting, because much waste grassland and unutilized land were not fully utilized to plant cassava, they would cause serious soil erosion. Its influence on other industries of cassava cultivation should be evaluated.
Suitability Evaluation of Camellia oleifera Planting Based on GIS Spatial Analysis in Guangdong Province

CHEN Qianqian
,XIE Dongdong,QIU Quan,ZHU Wen,GUO Yanqing

- , 2016, DOI: 10.6054/j.jscnun.2015.06.003
Abstract: 为加强广东省油茶种植区域布局合理性,提高油茶产业发展的可控性,以广东省油茶产业为研究对象,在利用气候因子、土壤因子、地形因子、数字高程模型(DEM)、科技支撑及育苗情况等数据分析的基础上,采用层次分析法对广东省油茶产业发展规划布局进行GIS适宜性评价. 结果表明:河源市、梅州市、清远市、韶关市、云浮市的西部、茂名市的北部、肇庆市的东部、阳春市及阳西县等地综合条件好,适合油茶产业的推广和开发.
: To strengthen the rationality of spatial distribution of Camellia oleifera planting area and promote the controllability of C.oleifera industry development in Guangdong province, based on GIS, data status on climatic factors, soil factors, terrain factors,digital elevation model (DEM), scientific support and seedlings cultivation collected from C.oleifera planting area in Guangdong province, the suitability of spatial distribution of C.oleifera industry in Guangdong province is evaluated by analytic hierarchy process. Results show that some regions are found to have good comprehensive conditions, such as Heyuan city, Meizhou city, Qingyuan city, Shaoguan city, western regions of Yunfu city, northern regions of Maoming city, Yangchun city, eastern regions of Zhaoqing city, Yangxi city, where are suitable for promotion and development of C.oleifera industry
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