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1.
In order to explore the regional variability of the effects of land use systems on soil properties, Shouyang County in Shanxi Province and Danling County in Sichuan Province of China were selected as the study areas. Field soil samples of the four land use systems (natural forest, forest plantation, shrubland, and cropland) were collected, respectively, from the two areas. The general statistical tools were used to analyze soil data. The results showed that the influence of land use systems on soil properties was significant. In general, soils in slightly human-disturbed land use systems presented a higher fertility level than those in strongly human-disturbed land use systems in both areas. Furthermore, the impacts of the same land use systems on soil properties showed a distinct regional variability, and even in the same land use system, different farming systems and site management measures (such as irrigation, fertilization, and pesticides) could also lead to the regional heterogeneity in soil properties. The regional variability of land use effects on soil properties reveals the regional variability of the effects of human activities on environmental changes, and could explain the complex relationship between humans and the natural environment in certain ways.  相似文献   

2.
The livelihoods of farmers are responding to the microeconomic policies and result in many changes in the landuse pattern and landscape, and the farmer's attitude to the natural resources conservation, specifically in the land degradation. In order to find the relationship between the farmers' response to the microeconomic policies and land degradation, the authors surveyed 120 household in three villages in the black soil zone in Heilongjiang Province. Based on the feedback of the questionnaires, the authors established a model to analyze the impact. The results demonstrated that land degradation was impacted by farmers behaviors in the process of the adjustment of agricultural structures in the city of Zhaodong. And the main factors acted on the land degradation were the agricultural labour education level, the transfer of the labour from agricultural production, the price of the agricultural production materials, and the land scale management. The authors put forward some suggestions for sustainable agriculture based on the analysis on the topic.  相似文献   

3.
The livelihoods of farmers are responding to the mioroeconomic policies and result in many changes in the landuse pattern and landscape, and the farmer's attitude to the natural resources conservation, specifically in the land degradation. In order to find the relationship between the farmers' response to the microeeonomic policies and land degradation, the authors surveyed 120 household in three villages in the black soil zone in Heilongjiang Province. Based on the feedback of the questionnaires, the authors established a model to analyze the impact. The results demonstrated that land degradation was impacted by farmers behaviors in the process of the adjustment of agricultural structures in the city of Zhaodong. And the main factors acted on the land degradation were the agricultural labour education level, the transfer of the labour from agricultural production, the price of the agricultural production materials, and the land scale management. The authors put forward some suggestions for sustainable agriculture based on the analysis on the topic.  相似文献   

4.
The study was conducted in four states of the Southwest geo-political zone in Nigeria and four regions in Ghana.. The results showed that the existing forest, agricultural and land use decree/policies in Nigeria and Ghana indicated lack of integration between Forestry and Agricultural land uses. The main conflicting areas were obsolete land use decree in Nigeria and lack of national land use policy in Ghana. The causes and effects of the conflicts had policy enunciation, stakeholders, and institutional and managerial dimensions. Some of the causes of the conflicts were lack of national land use policies for coherent and integrated forest and agricultural sectors; high population growth, de-reservation of forest reserves, unsustainable agricultural practices and technologies, land hunger, encroachment of forest reserves with cash crops and stakeholders' litany of demands and other diverse interests. Consequences of conflicts in the study locations included disharmony between forestry officials and farmers, antagonism between timber concenssionnaires and communities, wanton destruction of economic trees and seedlings, extinction of tree species, expansion of illegal farm lands and an attendant poverty. The logistic regression model for conflicts between forestry and agricultural land uses in Nigeria and Ghana indicated significant fit to the data judging from chi square value (df, 9) = 3174.1 that is significant at P 〈 0.05. The final loss of the model indicated a value of 92.47.  相似文献   

5.
《农业科学与技术》2013,(10):1517-1520,1525
The study has examined the tempo-spatial patterns of cultivated land use change in Jiangsu province. A principal component analysis (PCA) of 18 selected indicators of cultivated land use during the period 1970-2010 identified 2 main pat- terns of change in planting productivity and economic efficiency. A major shift from production-centered pattern to profit-oriented one occurred in 1984, the time of grain yield surplus and the mitigation of population pressure. In response to the impending Opened Market System, there was a notable tendency of higher efficiency and less productivity since 1997, as well as remarkable regional disparity of cultivated land use change spatially. It revealed a relative decrease in grain cropping share, crop- ping scale and cultivation intensity in South Jiangsu, especially in Tai-Lake region, and the reverse in North Jiangsu. Some suggestions for the future were finally dis- cussed from the above findings.  相似文献   

6.
以黔江区为研究对象,通过对生态环境影响因子的分析,发现制约黔江区土地利用环境发展的因素主要有区域气候变化、土壤要素、水文环境以及水土流失和土地退化等.并任以上分析的基础上,进一步分析了土地利用变化对生态环境的影响和制约黔江生态环境及区域发展的因素,最后提出了适应山区土地利用与生态环境协凋的对策,对黔江社会经济发展和生态建设具有重要意义. Abstract: Accompanying the development of social economy,the land use model of mountainous area,typically eco-weak area,is changing gradually.Here the establishment of eco-friendly land use model in mountainous area,will pioneer the model of sustainable development in that area.Concerning Qianjiang District of Chongqing Municipality,huge change of land use model,mainly embodied in the unceasing increase of construction land and gradual decrease of agricultural use land,has taken place in recent years.To explore the eco-friendly land use model in mountainous area,Qianjiang District was chosen as the study object in the present study.Via analyzing the changes in land use model,we found that related eco-environment restrictive factors mainly regional,climatic change,soil texture,hydrological environment as well as soil erosion and land degradation,etc.And based on these results,we further analyzed the effect of land use change on eco-environment and the factors restricting the maintenance of eco-environment and regional development,finally put forward the counter measures for balancing land use and co-environment in mountainous area.The results will be important for the development of social economy and eco-system construction in Qianjiang District.  相似文献   

7.
Monitoring and assessment of agricultural land degradation is of vital importance for better land and water management planning and reclamation. It requires setting baseline information and basic analysis at specific time and space. About 33 geo-referenced soil sampling spots were selected in two agricultural production locations in the Kingdom of Bahrain to assess the status and preliminary causes of land degradation. Soil samples were taken from 13 sites in Diraz location while 19 samples were taken from Budayyi location. The samples were taken to 90 cm depth at 30 cm intervals. Standard procedures were followed to determine soil physiochemical properties. In addition, field observations on farm condition, distance from the sea, method of irrigation and irrigation water source were taken. Some of the soil samples were deliberately taken from outside the irrigated basins among trees compared with samples taken from inside the actively growing area for comparison. The results indicated that the salinity level was significantly (P 〈 0.001) higher at the 0-30 cm soil depth compared with 30-60 cm or 60-90 cm depths in both locations. The distance from the sea did not show clear correlation with surface soil salinity in Budayyi area compared with Diraz. Both locations showed significantly higher salinity levels on samples taken outside the actively growing areas compared with those taken from within. The effect is more prominent at the 0-30 cm depth. The observed variability on salinity levels may be attributed to farm management practices and deteriorating quality of ground water. Thus, agricultural land degradation in Bahrain cannot be attributed to ground water deterioration alone. The use of tertiary treated sewage water (TSE) may ease the pressure on ground water, but the pH of the TSE should be carefully monitored and managed with proper studies on leaching requirements to avoid further salinity complications.  相似文献   

8.
Lepidopteran stem borers are the most damaging pests of maize in Sub-Saharan Africa. Despite the growing importance of maize in the forest zone of Democratic Republic of Congo, no data is available regarding stem borer pest species present and their relative importance. It is thus important to gather information likely to guide future research in this area. This study was undertaken to catalogue stem borer pest species identity and assess their relative infestation levels on maize. Surveys were carried out in wild and cultivated habitats in Kisangani. Five species were collected on maize, i.e., Sesamia calamistis Hampson (1910), Eldana saccharina Walker (1865), Busseola fusca Fuller (1901), Chilo sp. Strand (1913), and Mussidia nigrivenella Ragonot (1888). In the wild habitats, Poenoma serrata Hampson, B. fusca and S. calamistis were collected on Pennisetum purpureum whereas Chilo sp. was collected on Panicum maximum. Our results suggest that P. maximum might affect the population dynamics of Chilo sp. whereas P. purpureum is expected not to influence the population dynamics of other stem borers owing to its scarcity in the interior of the forest.  相似文献   

9.
The land ecosystem service function value contains the gas regulating function value, air purification function value, water conservation value, land conser-vation value, soil nutrient conservation value and maintain biodiversity value. Based on the method of market value and the data of Hubei Statistical yearbook, cultivat-ed land resources of ecosystem service function value is 730 038.69Mil ion in 2007-2009, and 714 774.99 Mil ion in 2010-2012 in Wuhan Metropolitan Area. After three years of development, Wuhan Metropolitan Area of ecological value of cultivated land has increased by about 3.97%. From the point of each composition, the im-portance of gas regulating function of cultivated land resources and water conserva-tion function is the forefront. From the point of spatial distribution, the highest of annual average value of the cultivated land ecological was Huanggang (1.725 bil ion yuan), the lowest was Ezhou (217.868 6 mil ion yuan) in 2010-2012. From the point of space changes, the land ecological value increased only in Qianjiang city, while farmland ecological value in other cities was fal ing The conclusion is of direc-tive significance to the regional land protection policy and the farmland reasonable distribution, for Wuhan Metropolitan Area and other areas.  相似文献   

10.
The East Eurasian Steppe Transect (EEST) is the ifrst international transect across regions of middle and high latitudes in the eastern Eurasian steppe. The EEST is an ideal platform for researching the response of Eurasian temperate steppe to global change, because of its integrated gradients of temperature and human activities on a large-scale. In this study, basic characteristics of plant communities along the EEST across a latitudinal gradient was analyzed. According to the survey of 58 sampling sites, there are 140 species belonging to 34 families and 94 genera. Of particular note was the ifnding of Astragalus dalaiensis which has disappeared in the grasslands of China. On the whole, Gramineae plants are dominant with Liliaceae plants in the communities signiifcantly decreasing along the latitudinal gradient from south to north. The Shannon-Wiener index and biomass of communities all decreased along the latitudinal gradient with signiifcant negative linear regressions. The SDR2 (summed dominance ratio based on two factors) of dominant plants in the upper layers of communities, such as Stipa and Leymus chinensis, decreased along the latitudinal gradient from south to north. Especially, the SDR2 of L. chinensis decreased signiifcantly. The SDR2 of Cleistogenes squarrosa, Agropyron cristatum in the lower layers of communities and the indicator species for degradation were not affected. Potentilla acaulis was found mainly in the southern and northern areas. Stellera chamaejasme was found just in a few sites in the southern area of the EEST. In communities of Stipa grandis and Stipa krylovii, annual and biennial species are dominant. The ratio of annual and biennial species in the community is signiifcantly related to the latitudinal gradient. Perennial herbaceous plants and shrubs were not affected. According to the principal component analysis (PCA), with the data from 58×140 dimensions, the ifrst and second components had the lowest proportion, thus indicating that the species compositions and community structures are homogeneous along the EEST. There is a certain degree of spatial differentiation along the EEST due to degradation’s differences resulting from the different land uses.  相似文献   

11.
土地利用/覆被变化(LUCC)研究现状与展望   总被引:13,自引:0,他引:13  
土地利用/覆被变化(land use-cover change,LUCC)是全球环境变化与可持续发展的重要研究内容,受自然、人文因素在不同时间、空间尺度上的相互作用。本文综述了LUCC在动态信息获取、过程模拟和驱动机制探讨、区域和全球模型建立、LUCC生态环境效应等方面所取得的进展。针对当前国内外LUCC研究中存在的一些问题,认为今后LUCC研究应加强构建综合的LUCC理论体系,土地利用变化数据融合以及完善LUCC模型功能等。  相似文献   

12.
谈兵  翟文侠  宋成舜  柯新利  陈志 《安徽农业科学》2012,(7):4129-4130,4164
运用土地利用类型动态度(UTD)和土地利用类型综合动态度(GTD)分析了西宁市土地利用变化的特点,同时结合Markov模型,分析了土地类型转换特点。结果表明,GTD为0.15%;UTD最大的是园地,最小是草地。耕地去向主要是城镇村及工矿用地,来源主要是其他土地和草地;林地去向是建设用地,来源为耕地和其他土地、草地;草地的去向是耕地和林地,没有来源;建设用地只有农村居民点整理为耕地转出,来源主要是耕地,比重占78.49%。总之,2015~2020年间,耕地比重先增后减,总体减少614.97 hm2;草地不断较少,减少329.91 hm2;建设用地不断增加,增加567.63 hm2。  相似文献   

13.
旨在了解人类活动对晋北地区土地利用/覆被变化(LUCC)的影响,为研究区合理利用土地资源、优化土地利用格局以及促进区域经济社会协调发展提供科学依据。利用晋北地区2008—2013 年的TM遥感影像数据,在ERDAS、ArcGIS 等软件的技术支持下,解译影像处理数据并建立土地利用变化转移矩阵,对研究区域近5 年来土地利用/覆被变化进行研究。结果表明:2008—2013 年期间,晋北地区耕地面积减少62561.10 hm2,林地增加55774.23 hm2,居民工矿建设用地增加22895.49 hm2,草地减少15395.60 hm2,水域面积增加1090.24 hm2,未利用地面积减少1803.29 hm2。这与研究区域在研究时段内大量退耕还林还草的生态建设、城镇化快速发展、经济持续增长等人类活动相关。综上,2008—2013 年期间,晋北地区土地利用与覆被发生了较大变化。  相似文献   

14.
本文通过对安徽省萧县1990年、2000年和2010年的三景Landsat TM遥感影像进行分析,结合研究区基本概况研究萧县土地利用/覆盖变化。根据研究目标,确定主要研究内容为:利用ENVI 4.7遥感软件对萧县不同时期的TM影像进行对比分析,解译土地利用/覆盖变化情况等遥感信息,分析并计算出土地利用/覆盖变化数据,将土地利用分为耕地、植被、水体、建设用地、未利用土地等五种类型。采用最大似然法分别对萧县1990年、2000年和2010年的三景Landsat TM遥感影像进行分类,然后进行对比分析,获取土地利用/覆盖变化的空间数据。在此基础上,利用数学统计分析方法,进行土地利用/覆盖变化动态分析。  相似文献   

15.
赵玲  徐永鹏 《安徽农业科学》2011,39(35):22102-22105
利用最小方差法将吉林省各县(市)的土地利用结构分为九大类型,包括耕园地主导类型区、林草地主导类型区、耕园地为主林草地为辅类型区、林草地为主耕园地为辅类型区、耕园地为主建设用地林草地为辅类型区、耕园地为主林草地未利用地为辅类型区、未利用地为主耕园地林草地为辅类型区、林草地为主耕园地未利用地为辅类型区和林草地主导其他地类均衡类型区,揭示了吉林省土地利用的空间规律,为吉林省土地资源利用战略的制定、农业区的规划发展,以及社会经济与生态环境的协调发展提供科学依据。  相似文献   

16.
[目的]探讨土壤碳库的变化规律。[方法]以原生高寒草甸、人工草地和农田(油菜地)作为研究对象,利用土壤有机碳密度分组法,研究3种土地利用方式对高寒草甸土壤有机碳(SOC)及轻组有机碳(LFOC)含量变化的影响。[结果]3种土壤0~40 cm土体内,SOC含量依次为人工草地>高寒草甸>油菜地,分别为113.13、111.61和93.54 t/hm2;LFOC含量依次为人工草地>高寒草甸>油菜地,分别为10.36、8.93和5.83 t/hm2。人工草地与高寒草甸相比,0~40 cm土壤SOC含量间差异不明显,但LFOC高16.01%;耕作20年的农田中,SOC和LFOC分别较高寒草甸低16.19%、34.71%。[结论]人工草地土壤中总SOC和LFOC则略高于高寒草甸,明显高于农田,人工草地和高寒草甸的植物-土壤系统的总固碳量明显高于农田。  相似文献   

17.
主要利用1986年土地利用类型矢量数据和2000年TM影像,研究文登市城市快速发展所发生的土地利用/覆被变化,研究结果表明:文登市土地利用以旱田、建设用地及林地为主,14a来,随着经济建设的发展,水田、旱田、林地、草地面积增加,其中草地及林地面积增加最多,分别为7.61km2和6.20km2,建设用地及水域面积减少。土地利用转移过程中,旱田7.95 km2转为林地,8.40 km2转为草地,水域向旱田、草地和建设用地分别转化5.66 km2、0.69 km2和0.45 km2。最后提出了土地利用可持续发展建议。  相似文献   

18.
根据1990、1999和2010年3期遥感数据获取吐鲁番绿洲土地利用的数据,对吐鲁番盆地绿洲的土地利用变化及其生态环境效应进行了定量分析。结果表明:1990—1999年由于草地和水域的转移面积减少的负贡献,导致区域生态环境指数下降,区域环境质量下降;1999~2010年耕地和草地转入面积增加的贡献,使区域生态环境指数上升,区域环境质量改善。近20年吐鲁番绿洲土地利用的环境效应明显,土地利用的生态环境指数上升,生态环境质量总体趋势上升,环境得到了改善。  相似文献   

19.
土地利用变化及驱动因素分析——以新疆乌苏市为例   总被引:4,自引:2,他引:2  
以新疆乌苏市为例,对该区土地利用变化及驱动因素进行分析.乌苏市1996~2006年间,土地利用数量变化较快.其中,耕地年变化率为6.31;,城镇及工矿用地年变化率为4.08 ;,林地年变化率为2.88;,交通用地年变化率为21.14;,园地面积年变化率为-8.03;,未利用土地年变化率为-3.29;,牧草地年变化率为1.05;.土地利用结构发生了较大变化,园地、水利设施用地和未利用土地占比分别减少了0.01;、0.24 ;和11.02;,其它用地类型占比均有增加.林地和牧草地占比增长较大,分别为2.83 ;和4.79 ;.对各项指标进行了相关分析、主成分分析和回归分析,对社会经济和自然驱动力的11个指标综合分析和对比,确定研究区土地利用变化的主要驱动因子,阐明干旱区绿洲土地利用变化的驱动机制,提出了该区土地可持续利用总体发展模式和分区调控方向与措施.  相似文献   

20.
王鸣雷  史文娇 《中国农业科学》2020,53(12):2435-2449
【目的】新增耕地的时空变化格局受气候变化和人类活动的双重影响,明确新增耕地时空格局变化及其驱动因素,为保障耕地资源和农业可持续发展提供指导。【方法】基于1980s—1990s、1990s—2000s、2000s—2010s 3个时段中国北方的新增耕地数据,利用重心转移模型和区域统计等方法,探讨中国北方新增耕地的重心变化以及时空格局变化;基于气候数据计算3个时段≥10 ℃积温(AAT10)以及标准化降水蒸散指数(SPEI),分析气候因素对耕地开垦的驱动作用;基于1980s以来的社会经济统计数据,结合空间叠加模型、区域统计模型等分析人为因素对耕地开垦的促进作用;综合气候和人为因素,结合地理分区的方法对中国北方的新增耕地进行分区。【结果】1980s以来,中国北方新增耕地重心呈现由东北向西北转移的态势;大多数耕地开垦地区的气候有暖干化趋势,2000年以来具有暖湿趋势的耕地开垦区比例逐渐增加;农业为主人口的增加、农业技术进步以及国家政策的影响为东北、新疆等地耕地资源扩张提供了必要的基础;新疆、黑龙江、吉林等地丰富的耕地后备资源以及平坦的地势条件为耕地开垦提供了可能;基于对气候和人为驱动因素分析,将中国北方分为7个分区,即东北北部气候驱动林草-耕地转换区、东北气候+人为驱动林草-耕地转换区、东北中部气候+人为驱动水旱转换区、北方气候+人为驱动林草-耕地转换区、黄土高原人为驱动生态恢复区、西北人为驱动荒地-耕地转换区以及新疆人为驱动绿洲农业开垦区。【结论】1980s以来,中国北方新增耕地时空格局表现出明显的差异性;暖干气候并未成为耕地开垦的限制因素,而较为湿润的气候在一定程度上促进了耕地的开垦;农业人口的增加、农业技术的进步以及国家政策的影响,对耕地开垦起到重要作用。  相似文献   

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