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1.
Africa's Albertine Rift region faces a juxtaposition of rapid human population growth and protected areas, making it one of the world's most vulnerable biodiversity hotspots. Using satellite-derived estimates of forest cover change, we examined national socioeconomic, demographic, agricultural production, and local demographic and geographic variables, to assess multilevel forces driving local forest cover loss and gain outside protected areas during the first decade of this century. Because the processes that drive forest cover loss and gain are expected to be different, and both are of interest, we constructed models of significant change in each direction. Although rates of forest cover change varied by country, national population change was the strongest driver of forest loss for all countries – with a population doubling predicted to cause 2.06% annual cover loss, while doubling tea production predicted to cause 1.90%. The rate of forest cover gain was associated positively with increased production of the local staple crop cassava, but negatively with local population density and meat production, suggesting production drivers at multiple levels affect reforestation. We found a small but significant decrease in loss rate as distance from protected areas increased, supporting studies suggesting higher rates of landscape change near protected areas. While local population density mitigated the rate of forest cover gain, loss was also correlated with lower local population density, an apparent paradox, but consistent with findings that larger scale forces outweigh local drivers of deforestation. This implicates demographic and market forces at national and international scales as critical drivers of change, calling into question the necessary scales of forest protection policy in this biodiversity hotspot. Using a satellite derived estimate of forest cover change for both loss and gain added a dynamic component to more traditionally static and unidirectional studies, significantly improving our understanding of landscape processes and drivers at work. 相似文献
2.
河南农区经济发展差异地理影响的小尺度分析 总被引：26，自引：2，他引：24
对中国第一农业大省河南的乡镇数据分析表明, 地理因素对农区经济发展具重要影响。 在较低经济发展水平的乡镇, 地形和农业资源条件具有显著的影响; 而在相对较高经济发展 水平的乡镇, 地理位置以及与此相伴生的基础设施条件的影响更为显著。模型分析表明, 地 形显著影响乡镇的人均收入, 而且随着收入的增加, 其影响程度递减。人均土地面积显著影 响非农产业发展水平较低的乡镇的人均收入。对非农产业比重低于20%的乡镇, 人均土地每 增加1 hm2, 人均收入就增加约96 元。地理位置影响着相关农区经济的发展, 尤其是对收入 较高的农区的影响十分明显。全省高收入乡镇的70%集中在河南中部地区, 正好与中原城市 群的空间范围相吻合。就单个乡镇而论, 离县城的距离显著影响高收入乡镇的人均收入。地 理因素对欠发达农区经济发展影响处于变动之中。随着经济水平的提高, 传统地理因素(如 地形、农业资源因素等) 的影响逐渐被对经济积聚有明显影响的地理临近性等要素的影响所 取代。因此, 不能简单的认为地理因素对经济发展的影响在下降。 相似文献
3.
基于城乡融合视角,通过多种渠道搜集镇域农民人均纯收入数据,分析黄河流域镇域经济的空间格局及其影响因素。具体而言,以农民人均纯收入为基础指标,以国镇比（全国城镇居民的平均收入与乡镇农民人均纯收入之比）、省镇比（省域城镇居民的平均收入与乡镇农民人均纯收入之比）、市镇比（市域城镇居民的平均收入与乡镇农民人均纯收入之比）、县镇比（县域城镇居民的平均收入与乡镇农民人均纯收入之比）为城乡融合下的镇域经济测度指标,分析黄河流域7 098个镇域单元组成的经济空间格局,进而探讨其影响因素。结果表明：（1）从国镇比下的城乡融合水平看,大多数地区的城乡收入差距较大,表明流域整体的城乡融合水平普遍较低。从空间分布看,低融合水平区主要分布在内蒙古以南、河南以西的广大地区并形成连绵集聚片区,高融合水平区主要分布在山东大部、河南中部及西部、内蒙古局部。省镇比、市镇比、县镇比下的空间分异格局与国镇比保持较高的一致性,不同的是随着参照指标的进一步缩小,各水平区集聚的程度有所弱化。（2）从空间关联格局看,国镇比、省镇比、县镇比下城乡融合发展水平的空间集聚效应明显,主要以显著高-高（HH）区、显著低-低（LL）区为关联类型。国镇比下的显著LL区分布在山东大部、河南中部及北部、内蒙古局部,而显著HH区集中出现在山西外围、甘肃、青海南部。（3）基于最小二乘法、空间滞后模型、空间误差模型等定量分析发现,整体分异格局主要受二三产业从业人员、建镇区人口占比、人均工业产值、二三产业从业人员占比的影响最为显著,工业生产总值、建镇区面积占比仅起基础性影响。 相似文献
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主成分分析法在新疆兵团经济可持续发展能力评价中的应用 总被引：1，自引：0，他引：1
采用多元统计主成分分析方法对新疆兵团13个师1991～2006年的各师农场职工家庭人均纯收入、人均农业增加值、人均工业增加值、人均第二产业增加值、人均GDP等11个经济指标进行分析计算并且对各师的综合经济可持续能力进行比较。结果表明：从原始数据中提出占总方差86．6％的4个因子来反映各师的经济可持续发展程度,经分析发现影响各师的4个主成分因子：（1）人均GDP、人均工业增加值（包括第二产业、第三产业的增加值）的因子控制;（2）人均新增固定资产、人均固定资产投资等反映人均资产投入的综合指标;（3）反映人均耕地面积、人均利润、人均社会消费品零售总额的综合指标。（4）反映人均农业增加值、人均固定资产投入及人均社会消费品零售总额的综合指标。然后将各主成分得分结合主成分权重进行计算得出各师经济可持续能力值,其中农一师排在第一。从总体上看1992～2006年各师经济可持续发展的综合指标趋势是逐渐上升的,发展具有可持续性。, 相似文献
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Over the past few decades, land use and land cover change has become a global concern. In the Lop Buri province of Thailand, rapid land cover change, specifically conversion of forests to agriculture, has occurred. The purpose of the study is to identify the predictors of land cover change in Lop Buri province for land that has been converted to upland crops or has undergone deforestation between 1989 and 2006. Four logistic regression models were constructed using spatially explicit biophysical and geo‐social data, to account for changes to upland crops and forest loss from1989–98 and 1998–2006. Across the four models, slope, distance to forest edge, distance to towns, distance to roads, population size, and population density in various stand‐alone and interactive forms were found to be the most consistent predictors of land cover change. 相似文献
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山区合适耕地经营规模确定的实证研究——以重庆市为例 总被引：1，自引：0，他引：1
在地形起伏、地块破碎、分布半径较远等约束下,山区多大的经营规模是合适的?这是目前必须弄清的科学问题之一。使用480份有效调查问卷,以投入农业的劳动力为测算单位,以劳均纯收入为评价指标,分作物类型和地块分布半径,构建计量经济模型,测算不同条件下合适的耕地经营,结果表明：① 在现有社会经济条件下,样本村农业土地适度规模经营面积为24~32亩,适度规模下的劳均纯收入远高于当前农村人均纯收入,且与城镇居民的差距明显缩小。② 作物类型对适度规模影响不大,但对农民纯收入产生较大作用。经济作物和粮食作物的适度规模分别为24.33亩、24.63亩,差异不显著,但种植经济作物和粮食作物在适度规模下的劳均纯收入相差3638元,巨大的差距将促使经济作物种植面积不断扩大。③ 距离对适度规模影响较大,但对劳均纯收入影响不大。0.5 km内、0.5~1 km的适度规模分别为28.62亩、31.83亩,单位劳动力的适度规模相差3亩,这表明距离是目前从事农业生产时劳动力投入时须考虑的重要因素。但是,对应的劳均纯收入相差较小,又说明伴随耕作距离的增加,更多的投入主要依靠机械来完成,从而带动适度规模的扩大。1 km外的建模未通过检验,也进一步说明未实现规模经营、没有进行机械化耕作、离家远的土地收支严重不平衡,撂荒严重,规模化经营、机械化耕作是解决距离问题的有效途径。本文得出的土地适度规模是可行的,也验证了推进土地适度规模经营的可行性和必要性。 相似文献
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This study explores the main direct and underlying causes of deforestation in Brazil's Legal Amazon region by considering spatial differences. The computation of localized parameters is based on geographically weighted regression (GWR). The novelty of this paper lies in its incorporation of economic, rather than Euclidean, distances into the GWR. Economic distances are measured by travel time, sourced from Google Inc. A global approach revealed several important factors that affect deforestation, including: rural population, GDP (suggesting a U-shaped environmental Kuznets curve), forest stock, cattle ranching, timber value, and road networks (both official and unofficial). Local analysis uncovered patterns not seen under global models, especially in the state of Pará. Most notably, crop cultivation was found to accelerate deforestation in southeastern Pará and northeastern Mato Grosso, while in some regions (especially in the northeastern corner of Pará), the area covered by crop plantations was negatively associated with deforestation. For Pará, rural credit constraints, larger territories designated as sustainable use areas and indigenous lands, and higher levels of precipitation inhibit deforestation. Further, rural population has a very heterogeneous impact on deforestation across Legal Amazon: it is not a significant factor of deforestation in northern Pará and Amapá, but it has a relatively strong effect in the western parts of Mato Grosso and Rondônia. Also, official and illegal roads create significantly more pressure on forests in remote regions compared to developed areas. Finally, the use of economic distances, as opposed to Euclidean distances, leads to notably different GWR results. 相似文献
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中国典型旅游上市公司业绩与区域经济的关系 总被引：6，自引：0，他引：6
从市场构成的角度来研究中国典型旅游上市公司的不同层次市场域中经济发展水平、人口数量对其业绩的影响,我们发现典型旅游上市公司属地省份的经济发展水平会对其业绩有显著的影响,相邻省份经济发展水平的影响程度要小于景点属地省份,而次相邻省份经济发展水平对典型旅游上市公司业绩没有显著的影响。这个结论与旅游系统距离衰减规律是相一致的。当保持经济发展水平等其他控制变量不变的情况下,在不同层次市场域中,单纯的人口增加并不会对典型旅游上市公司的业绩有显著影响。 相似文献
9.
采用 2000、2005、2010、2015 年 4 期土地利用/土地覆盖遥感解译数据以及新疆水资源公报 和统计年鉴资料,旨在评价新疆沙产业与水资源承载力状况。通过计算未利用土地转化成农地、 林地、草地的数量,分析 16 a 来新疆沙产业发展状况,结合水足迹模型和区域水资源承载力评价指 标,计算新疆 2000—2015 年水足迹,对区域水资源承载力进行评价。结果表明：（1）2000—2015 年 间,随着新疆人口增长和经济的发展,新疆沙产业发展迅速,部分沙地、戈壁等未利用土地和草地 被开发成耕地、林地、工矿和城镇及农村居民用地。（2）新疆水足迹整体呈上升趋势,水足迹以消费 农产品水足迹占主体,且消费农产品水足迹量快速增加,主要原因是新疆地区大力发展沙产业,利 用未利用土地、草地进行植物、沙生药材种植。（3）新疆人均水足迹、水资源压力指数、水足迹效益 指标呈现增加趋势,但数值明显低于我国人均水平。新疆社会经济发展总体趋势向好,但水资源 利用方式仍然比较粗放,水资源未得到合理开发。因此,新疆应采取优化产业结构、调整农作物种 植比例和用水结构,以增大水资源所支撑的沙产业发展规模,研究可为区域产业结构及消费模式 调整提供依据。 相似文献
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东北三省城乡收入差距空间格局及其分异机制研究 总被引：6，自引：4，他引：2
借助多元逐步线性回归、GWR等模型方法,探讨1990年以来东北三省城乡收入差距空间格局、类型特征及其分异机制,最后提出城乡统筹可持续发展建议。结果表明： 1990年以来,东北三省城乡居民收入水平大幅提高,但大部分地区城镇居民可支配收入水平仍低于全国平均水平;城乡收入差距整体有所拉大,呈现出“中间高、两端低”的空间特征。 城乡收入差距空间分布格局受经济发展水平、工业拉动效应、服务业带动力和交通通达程度影响,其中经济发展水平对城乡收入差距由早期的正向拉大作用为主,逐步演变为负向抑制效应。 据此提出对策建议：深化改革开放,加快国有企业改革步伐,优化区域产业结构,提高服务业发展水平和比重,激发市场活力,破解制约区域经济发展的各种障碍;加快实施乡村振兴战略,促进乡村资源开发,开辟致富增收新路径。 相似文献
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西藏自治区农牧民收入结构分析 总被引：2，自引：1，他引：1
依据入户调查资料 ,文章重点分析了现阶段西藏农牧民的收入结构 ,包括收入来源、收入性质、现金收入等内容 ,探索了不同地区 (农区、牧区、半农半牧区、一江两河农业开发区、城郊区等 )及不同收入段农牧民收入结构和收入来源的差异。通过分析发现西藏农牧民收入有以下特征 :①收入以实物为主 ,现金收入和可支配收入少 ;②城郊区农牧民收入多样化指数高 ,农牧民收入高 ,收入多样化指数与农牧民收入正相关 ;③低收入农户收入来源单一 ,抗风险能力弱 ,收入增加困难 ;④从生活质量看农区优于牧区 ,半农半牧区农牧民生活质量最差 ;⑤影响农牧民人均收入的主要因子为人均生产性投入、区域通达度等。 相似文献
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中国森林资源动态变化的社会经济学初步分析 总被引：23，自引：5，他引：18
从回顾建国以来中国森林资源的变化历程入手,计算了不同时段的森林采伐率,并在此基础上分析了影响森林资源动态变化的社会经济因素。其中工业用材和燃料、薪柴是导致高森林采伐率主要因素;人口数量及人口密度和经济发展水平是制约森林资源消长的重要因子。 相似文献
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针对当前温室气体排放影响因素研究中忽视工农业生产排放源的现状,在对福建省2001―2010年各类温室气体排放量进行核算,并统一转换成CO2当量的基础上,通过引入能表达工农业生产过程自身温室气体排放的新指标,建立改进后的对数Divisia均值分解模型（LMDI）对福建省温室气体排放的影响因素进行分解分析。研究发现：2001―2010年福建省温室气体排放量不断上升,但环比增长率整体波动下降;产业结构、经济规模、人口规模、能源结构、人均收入、城市化水平、城市居民工业强度等因素的累积效应对温室气体排放增加有正向促进作用,其中城市居民工业强度的贡献率达到了13.66%;能源强度、农业生产强度的累积效应对温室气体排放有负向抑制作用,其中农业生产强度累积效应占负向效应总和的50%以上。研究结果显示：工农业生产过程对福建省温室气体排放有显著的驱动作用,不应忽视。 相似文献
14.
中国草食家畜养殖的时空动态及其影响因素 总被引：1，自引：0，他引：1
发展草食家畜养殖是推动中国耗粮型畜牧业向节粮型畜牧业转型、解决人畜争粮矛盾的关键。本文运用探索性空间数据分析技术和计量模型方法,系统考察了中国草食家畜养殖的时序变化过程、地理集聚特征及其影响因素。研究表明：① 中国草食家畜养殖量整体增长态势明显,但畜种间养殖量存在较显著的差异。1978-2012年中国草食家畜养殖量增长了92.5%;同期养殖量肉牛>肉羊>奶牛。② 县域尺度上,草食家畜养殖量增长区数量多于减少区,而且北方地区养殖量增长明显快于南方地区,初步形成了“北热南冷”的空间格局。③ 空间杜宾模型显示,人均粮食产量、生产性土地面积比重、城镇人均可支配收入、农业机械化水平、农业劳动生产率与政策因素五项指标,对草食家畜养殖的发展有着正向效应,而人均GDP、城镇化水平和非农收入比重有着显著的负向效应。④ 中国草食家畜养殖可划分为6大类型区,各类型区应根据“区情、农情”从不同的侧重点加以调控。此外,还应优化调整区域种养结构、实行差别化的区域发展对策及重视养殖集聚区非农产业发展,稳定、促进草食家畜养殖业的发展。 相似文献
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16.
河西走廊景观类型变化的社会经济驱动力研究 总被引：26，自引：14，他引：12
利用1995和2000年两个时期的Landsat5的4、3、2(RGB)波段合成影像解译结果, 采用中国科学院资源环境数据库中的全国1∶10万土地资源利用分类系统, 对河西走廊近5年来景观动态变化的驱动力进行了研究。为判断出区域景观类型变化趋势, 研究从区域背景变化格局分析入手, 对区域内部变化斑块的几何特征、变化数目及与GDP的对应关系进行统计分析, 得出河西走廊景观变化和社会经济发展具有较高的时空相关性, 进而用典型相关分析方法来推导了斑块变化的内在社会经济驱动力。结果表明: ①引起耕地斑块转出的因子是农牧投入-产出的增加, 水域斑块转出直接与渔业产值有关, 未利用地斑块转出与农业机械的使用和播种面积增加相关, 林地斑块转出的因子是农业产量和工业产值的变化, 城建斑块转出与农民收入低、城市化水平有关; 城镇用地斑块转入是工业产值增加的结果, 草地、林地斑块转入的因子是农业投入的增加, 耕地斑块转入与农民收入增加有关, 水域斑块转入直接因子是渔业产值增加。②结合驱动力类型分析, 耕地面积变化主要是最优经济福利及粮食安全驱动作用下的结果; 草地、林地被开垦, 耕地增加主要是生存型经济福利驱动的结果, 最优经济福利驱动有时也起到一定的作用; 城镇用地增加主要是最优经济福利驱动的结果; 在生态环境脆弱及其 相似文献
17.
Population growth and land use in Nepal: "the great turnabout" 总被引：1，自引：0，他引：1
Historically, Nepal has demonstrated a "great turnabout" trend, in which initial immigration from the lowland areas to the mountains has been replaced by accelerating migration from the hills to the plains. The reason for this reversal has been a rapid growth in population within the confines of limited availability of potentially cultivable land. Given Nepal's slow economic development, the overwhelming majority of increases in population have to be accommodated within the agricultural sector, on which 83% of Nepal's households are dependent. Fundamental land use issues in Nepal include rapid achievement of the final limit of land suitability for cultivation and the speed at which land can be brought into cultivation. The Government of Nepal has developed the objectives of increased food production to provide a satisfactory diet for the population, increased per capita income, improved regional balance in income and development, conservation of natural resources such as land and forests, and overall development of the economy through income generation, export earnings, and release of agricultural labor to other sectors. 3 perspective studies have identified a number of policies and programs that could bring Nepal closer to these goals. These studies analyzed potential land use development, agricultural production, and food availability by the year 2005. Most essential is the need to intensify land use not only in crop agriculture, but also grasslands and forest use. Land must be allocated to uses that represent the most productive use of that land without being degrading. Technologies are available for land use in each of the main types of uses--crop agriculture, livestock, and forests--that can provide protection against land degradation. Finally, irrigation is a key element in raising agricultural output. Close cooperation between the government and the people is crucial for the success of the task of finding a balance between population growth and its demand for services of the land. 相似文献
18.
随着“西部大开发”战略的深入实施,西部地区已经成为我国经济发展最快的区域,然而西部经济的快速增长已经造成了碳排放量的犬幅增加,严重影响了我国节能减排目标的实现。为了有效地控制西部地区碳排放量的急速增加,我们必须全面分析引致西部碳排放量增加的主要因素。本文在已有研究的基础上,从西部地区产业转型和消费升级的视角出发,利用1991—2009年的省际面板数据对西部地区的经济发展模式与碳排放量增长之间的相关关系及其传导机制进行了实证检验。检验结果表明：自进入上世纪90年代以来,西部地区的经济发展与碳排放量增长之间存在显著的正相关关系,而且在西部大开发战略实施以后,这种关系更加显著。同时,检验还发现西部地区的消费升级和产业转型对碳排放量增加产生重要影响,其中三次产业间结构变动的影响系数达到16．4,二次产业内部采掘业和重工业比重上升的影响系数达到14．3,人均居住支出和人均交通支出的影响系数也分别达到5．6和6．5,而传统的人口规模、收入规模则对西部地区碳排放量的影响微弱。影响系数仅为0．73和0．86。因此在制定西部地区“十二五”节能减排战略时,需要更多的从消费升级和产业转型的视角出发。 相似文献
19.
With the promotion of agricultural ecological civilization construction in China, agricultural ecological security has received increasing attention. How to ensure agricultural ecological security has become a great concern for many scholars. As an important agricultural province in China, Hubei is of great significance to Chinese food security and agricultural sustainable development. This paper aims to establish an index system of agricultural ecological security and security classification of Hubei via Analytic Hierarchy Process and Pressure-State-Response methods. An evaluation of agricultural ecological security in Hubei, with a base of the national average value in 2015, reveals that the security degree has increased by 0.07566 from 0.90150 in 2005 to 0.97716 in 2015. Results show that agricultural ecological security in Hubei has improved but failed to reach the national average and there is still large space for improvement of the security level, considering a trend of deterioration in some indexes, such as per capita water resources, population density, per unit area pesticide load of farmland, forest coverage, grassland degradation rate and average annual precipitation. Influencing factors, especially population spatial distribution, misconduct in agricultural production, insufficient ability in agricultural natural disaster prevention, deficiency of agro-ecological technology of agricultural ecological security in Hubei are analyzed. For improvement of the degree of agricultural ecological security in Hubei, some countermeasures and suggestions are discussed. 相似文献
20.
The development of grass-feeding livestock breeding is the key to promoting the transition from grain-consumption type animal husbandry to grain-saving type animal husbandry in China, and to solving the problem of competition for grain between people and livestock. From the perspective of economic geography, this paper first defines the conversion standard for the breeding quantity of livestock, and then uses exploratory spatial data analysis technology and econometric models and methods to systematically investigate the sequential variation process, geographical aggregation characteristics, and influencing factors of grass-feeding livestock breeding in China. The study results show the following: 1) The breeding quantity of grass-feeding livestock in China has an obvious overall growth trend, but there is an obvious difference among the livestock species. During the period 1978–2012, the breeding quantity of grass-feeding livestock in China grew by 92.5%; and the breeding quantity within the same period was beef cattle > sheep > dairy cow. 2) On the county scale, the number of increasing areas of the breeding quantity of grass-feeding livestock is larger than the number of decreasing areas, and the growth rate of breeding quantity of grass-feeding livestock in northern China is higher than that in southern China, which initially forms the pattern of “hot in the north and cold in the south”. 3) The spatial Durbin model shows that the per capita output of grain, proportion of productive land area, urban per capita disposable income, agricultural mechanization level, agricultural labor productivity and policy factor have positive effects on the development of grass-feeding livestock breeding, while the per capita GDP, urbanization level and proportion of non-agricultural income have obvious negative effects on it. 4) Grass-feeding livestock breeding in China can be divided into six major types of areas, and each type of area should be regulated and controlled in terms of their respective focus of attention according to regional conditions and situation of agricultural production. 相似文献