22 resultados para land evaluate system

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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土地利用是人类根据土地质量特性来开发利用土地,创造财富,满足人类生产和生活的需要,同时改善环境,满足人类生存需要的过程。土地利用总体规划是对未来各类用地在空间上、时间上作出总体的协调的预先安排,不仅受到一定历史背景的制约,同时也受影响于当前的社会经济发展情况。但是,国内传统的土地利用总体规划往往从狭窄的技术经济观点出发,对远期的生态环境问题、社会问题缺少考虑,将新的用地尽量安排在最便捷、最经济的地方。 由于土地利用总体规划对环境影响具有长期性、复杂性、综合性、有时还有不可逆转性等特点,迫切需要在编制土地利用总体规划时对规划区与土地利用有关的环境影响进行科学研究,把环境保护纳入土地利用活动的计划、决策和规划实施中,促进土地资源持续、协调的利用。为更好地进行土地利用总体规划环境影响评价必须首先建立相应的评价指标体系,而目前国内关于该项研究的理论和实践的相关报道都较少。 本论文在综述国内外土地利用总体规划环境影响评价的理论与实践的基础上,在国内第一批开展了相关领域的案例研究,采用理论研究和案例分析相结合的研究方法对土地利用总体规划环境影响评价方法和指标体系进行了研究,对邛崃市土地利用总体规划进行了环境影响评价,其研究的主要内容和论点如下: (1)第一次根据FAO 确定的五大原则,引入了生态用地的概念并按照价值模型构建了以土地资源可持续利用为目标的县级土地利用总体规划环境影响评价的指标体系。以生产性、稳定性、保护性、经济活力、社会可接受性五个方面作为指标层来度量土地利用总体规划的环境影响,并选取了土地利用率、土地整理率、水面指数、生态用地面积比例、耕地转化率、建设用地产值指数、公众满意度等21 个元指标作为具体的评价指标。该指标体系强调了规划方案的公众参与,便于充分吸收公众的意见和建议;并且评价指标获取容易,实用性较强。 (2)在土地利用总体规划环境影响评价方法上进行了有益的探索和尝试,由于土地利用总体规划环境影响评价的主要对象是几个拟定的规划方案,所以采用综合评分法(包括特尔斐法和层次分析法)和公众参与相结合的评价方法。应用上述指标体系和评价方法对邛崃市土地利用总体规划的三个方案进行了评价筛选,高方案最终得分为92.049;中方案最终得分为91.028;而低方案最终得分为95.541,为最优方案。 (3)开展了对土地利用总体规划替代方案和公众参与机制的研究,对公众参与的方式、程序及主要内容从理论和实践两方面进行了有益的尝试,收到了良好的效果。 (4)对邛崃市土地利用总体规划进行了环境影响评价,根据邛崃市的具体情况,对规划实施后可能造成的环境正、负面影响进行了分析和预测,提出了预防或者减轻不良环境影响的对策和措施。 Land use is a process, which is to develop land according to its mass property. Bycreating the wealth and improving the environment, it can meet the need of production,life and human survival. Land use planning, as a planning form to guide land use, issubject to the historical background, and influenced by development of economic andsociety. The land use planning in the past, from narrow economic technology view,lacking of concerning ecologic environmentand social problem, arranged new land in the most convenient and economic place. Because of complexity, comprehensive and sometimes irreversible characteristicsof environmental impact caused by land use planning which has been implemented, it isneed to carry on scientific research on environmental impact related to land use as theland use planning is forming, to bring environmental protection within the plan, policymaking and implementing of land use activity, promoting the sustainment, harmonious use of land resource. This paper, taking the readjustment of land use planning in Qionglai as an example,assessed its environmental impact of land use planning. The main contents and results arepresented as follows: (1) On the basis of the five criterions of AFO, for the first time propose county classoverall planning of land uses SEA index by inducting ecological land use andestablishing the Value factor system, according to Productivity criterion,Stabilitycriterion,Sheltered criterion,Economic livingness criterion,Social acceptabilitycriterion,the environmental impact of land use system was assessed by using Valuemodel. Through identifying the factors of environmental impact of land use planning, thepaper established the factor system of SEA of land use planning. From the land usefactors, 21 factors was chosen to assess the environmental impact degree of land useplanning, such as, index of land use degree, the rate of land collating, index of watersurface, the rate of ecological use land, cultivated land conversion ratio, forest landconversion ratio, public satisfaction degree and so on. These indexes make a point thatpublic participation of plan project fully absorb public idea and propose and the index easily get, better utility. (2) Attempt useful assessment method system of SEA of land use planning. In viewof there are no or almost no inevitable contact among the factors of SEA of land useplanning,we use AHP (Analytic Hierarchy Process) as the main assess method . Thereare three plans are compared in this paper apply the foregoing index and assessmentmethod. The high plan finally score is 92.049,while the middle plan is 91.028. The lowplan score is 95.541,is the best one,as the selected plan. (3) Carry on the research of the alternative scheme of overall planing of land useand public participation,to the fashion ,procedure and object matter carry out helpfulattempt from theory to practice,the results is good. (4)Took place SEA of Qionglai County overall planing of land use,according to thecircumstance of Qionglai,we analyze and forecast the positive and negative affect afterthe plan implement,and put forward the countermeasure and means to prevent or abatebad environmental impact.

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植被覆盖对陆地生态系统的水分循环起着重要作用。径流对植被变化在不同时间尺度的响应研究,对区域生态环境建设及水资源管理具有重要的参考价值。该文介绍基于对比流域法,在多年平均、年际、季节等不同时间尺度径流对植被变化响应的研究结果。多年平均尺度上,由植被类型更替引起的径流绝对变化量,湿润区较干旱区大,其相对变化量在干旱区严重;年际尺度上,因植被变化,径流从一种平衡状态到另一种平衡状态的响应时间因抚育措施和地区不同而不同,造林情况下,湿润地区一般需要15~20 a,干旱地区约需25 a甚至更长,森林自然恢复情况下则需要上百年;季节尺度上,径流对植被变化的响应在季风影响区较四季湿润地区强烈。流量历时曲线研究表明,干旱地区造林,其基流无论在量或发生概率的变化上均较湿润区强烈。

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Jiyang & Changwei depressions are two neighboring depressions in Bahai Bay Basin, the famous oil rich basin in East China. The exploration activities in the past 40 years has proved that, within the basins, there exists not only plentiful sandstone hydrocarbon reservoirs (conventional), but also abundant special reservoirs as igneous rock, mudstone and conglomerate ones which have been knowing as the unconventional in the past, and with the prospecting activity is getting more and more detailed, the unconventional reservoirs are also getting more and more important for further resources, among which, the igneous lithological reservoir be of significance as a new research and exploration area. The purpose of this paper is, with the historical researches and data as base, the System Theory, Practice Theory and Modern Comprehensive Petroleum Geology Theory as guide, the theoretical and practice break through as the goal, and the existing problems in the past as the break through direction, to explore and establish a valid reservoir formation and distribution models for igneous strata in the profile of the eastern faulted basins. After investigating the distribution of the igneous rocks and review the history of the igneous rocks reservoirs in basins, the author focused on the following issues and correspondingly the following progresses have been made: 1.Come to a new basin evolution and structure model named "Combined-Basin-bodies Model" for Jiyang even Eastern faulted basins based on the study on the origin and evolution of Jiyang & Changwei basins, depending on this model, every faulted basin in the Bo-hai Bay Basin is consisted of three Basin-Bodies including the Lower (Mesozoic), Middle (Early Tertiary) and the Upper (Late Tertiary) Bodies, each evolved in different geo-stress setting and with different basin trend, shape and igneous-sedimentary buildings system, and from this one to next one, the basin experienced a kind of process named "shape changing" and "Style changing". 2. Supposed a serious of new realizations as follows (1) There were "multi-level magma sources" including Upper mantel and the Lower, Middle and even the Upper Shell magma Chambers in the historical Magma Processes in the basins; (2) There were "multi-magma accessing or pass" from the first level (Mantel faults) to the second, third and fourth levels (that is the different levels of fault in the basin sediment strata) worked in the geo-historical and magma processes; (3) Three tectonic magma cycles and more periods have been recognized those are matched with the "Basin -body-Model" and (4)The geo-historical magma processes were non-homogeneous in time and space scale and so the magma rocks distributed in "zones" or "belts". 3. The study of magma process's effect on basin petroleum conditions have been made and the following new conclusions were reached: (1) the eruptive rocks were tend to be matched with the "caped source rock", and the magma process were favorable to the maturing of the source rocks. (2) The magma process were fruitful to the accumulation of the non-hydrocarbon reservoirs however a over magma process may damage the grade of resource rock; (3) Eruptive activity provided a fruitful environment for the formation of such new reservoir rocks as "co-eruptive turbidity sandstones" and "thermal water carbonate rocks" and the intrusive process can lead to the origin of "metamorphism rock reservoir"; (4) even if the intrusive process may cause the cap rock broken, the late Tertiary intrusive rocks may indeed provide the lateral seal and act as the cap rock locally even regionally. All above progresses are valuable for reconstructing the magma-sedimentary process history and enriching the theory system of modem petroleum geology. 4. A systematic classification system has been provided and the dominating factors for the origin and distribution of igneous rock reservoirs have been worked out based on the systematic case studies, which are as follows: (1) The classification is given based on multi-factors as the origin type, litho-phase, type of reservoir pore, reservoir ability etc., (2) Each type of reservoir was characterized in a detailed way; (3) There are 7 factors dominated the intrusive reservoir's characteristics including depth of intrusion, litho-facies of surrounding rocks, thickness of intrusive rock, intrusive facies, frequency and size of the working faults, shape and tectonic deformation of rock, erosion strength of the rock and the time of the intrusion ect., in the contrast, 4 factors are for eruptive rocks as volcanic facies, frequency and size of the working faults, strength of erosion and the thermal water processing. 5. Several new concept including "reservoir litho-facies", "composite-volcanic facies" and "reservoir system" ect. Were suggested, based on which the following models were established: (1) A seven reservoir belts model for a intrusive unit profile and further more, (2) a three layers cubic model consisted of three layer as "metamorphic roe layer", "marginal layer" and "the core"; (3) A five zones vertical reservoir sequence model consisted of five litho-facies named A, B, C, D and E for a original lava unit and furthermore three models respectively for a erosion, subsidence and faulted lava unit; (4) A composite volcanic face model for a lava cone or a composite cone that is consisted of three facies as "crater and nearby face", "middle slope" and "far slope", among which, the middle slope face is the most potential reservoir area and producible for oil & gas. 6. The concept of "igneous reservoir" was redefined as the igneous, and then a new concept of "igneous reservoir system" was supposed which means the reservoir system consisted of igneous and associated non-igneous reservoirs, with non-hydrocarbon reservoir included. 7. The origin and distribution of igneous reservoir system were probed and generalized for the exploration applications, and origin models of the main reservoir sub-systems have been established including those of igneous, related non-igneous and non-hydrocarbon. For intrusive rocks, two reservoir formation models have been suggested, one is called "Original or Primary Model", and the another one is "Secondary Model"; Similarly, the eruptive rock reservoirs were divided in three types including "Highly Produced", "Moderately Produced" and "Lowly Produced" and accordingly their formation models were given off; the related non-igneous reservoir system was considered combination of eight reservoirs, among which some ones like the Above Anticline Trap are highly produced; Also, the non-hydrocarbon. Trap system including five kinds of traps was discussed. 8. The concept models for four reservoir systems were suggested, which include the intrusive system consisted of 7 kinds of traps, the land eruptive system with 6 traps, the under water eruptive system including 6 kinds of traps and the non-hydrocarbon system combined by 5 kinds of traps. In this part, the techniques for exploration of igneous reservoir system were also generalized and probed, and based on which and the geological progresses of this paper, the potential resources and distributions of every reservoir system was evaluated and about 186 millions of reserves and eight most potential non-hydrocarbon areas were predicted and outlined. The author believe that the igneous reservoir system is a very important exploration area and its study is only in its early stage, the framework of this paper should be filled with more detailed studies, and only along way, the exploration of igneous reservoir system can go into it's really effective stage.

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The historical land use and land cover changes is one of the key issues in LUCC research. However, the achievement of China in this field doesn't match her position in the world yet. And the reliability of the quantitive records in Chinese historical literature, the basic data for historical land use research, has been doubted. This research focuses on Re-Cha-Sui, a typical area for the farming-pastoral region in the north of China, to make a detailed case study in this field. Based on a deep mining and calibration on the data from massive historical documents and land-use surveys, the author gives a detailed analysis on the administrative region evolution, historical population dynamics, reclamation policy, and the land statistic system. According to textual researches, parallel validation and physical geographical analysis, a unified land use series for recent 300 years, which founded on the results of modern land-use surveys, is constructed. And the thematic maps on the cultivation index for different counties in several temporal sections are plotted. Based on the endeavor above, the dynamic of forest and steppe is reconstructed as well. The temporal-spatial patterns of land use/land cover changes in the area is analyzed. And the influence of different driving forces are discussed. The main conclusions of the research are as followed: 1. The quantitive records in literatures on Re-Cha-Sui area are reflection of real amounts of croplands. It is practical to reconstruct a result comparable with the modern land-use surveys, based of a deep mining and considerate validation on historical documents. The unexceptional negative attitude towards the numerical records in historical documents is unnecessary. 2. In recent 300 years, 3 climax of reclamation appeared in Re-Cha-Sui area and altered the pure pastoral area into a farming-pastoral region. The interval were respectively the early time till mid time of the Qing dynasty, the end of the Qing dynasty till early time of the Republic of China(ROC), and the time after A.D. 1949. After the first expansion, the area of cropland in this region reached 2.0 million ha. Among them, Guisui area, which was most densely cultivated, had a cultivation index over 30%, which is similar with modern situation. The second expansion covered broader area, and the amount of cropland reached 3.5 million ha. The increase of farming area after 1949 is due to the recultivation of abandoned farmland. The current area of cropland in this region is 5.6 million ha. In the southern area where the land was reclaimed early, the amount on of the cropland has some fluctuation in 300 years. While in the new reclaimed area in the north, the area of cropland has kept the trend of increasing. 3. Due to the different natural conditions, most forests in Re-Cha-Sui area distribute in the mountain area of North Hebei province, and the upland of West Liaoning province, especially the former, which has a forest coverage near 70%. However, most of these forests were destroyed before the end of the Qing dynasty. In 1949, the natural forest near Chengde was nearly cleared up. They were partly renewed after 1949 due to plantation. 4. In the steppe zone such as northern Rehe, Suiyuan and Chahar, the area of steppe has a negative correlation with that of cropland. With the expansion of cropland, the percentage of steppe has shrunk from over 80% to 53%. In the mountain area of North Hebei province, steppe expanded with the shrinkage of forest, though cropland was expanding. The percentage once reached 60%, and then fell with the renew of forest. However, in the upland of West Liaoning province, the steppe shrink slowly from original 50% to current 26%, with the expansion of cropland. 5. The land use and land cover change in Re-Cha-Sui area in recent 300 years is driven by various factors, including human dimensions such as population, policy of the government, disorder of the society, cultural tradition, and natural factors such as climate change and natural disasters. Among them, pressure from surplus population is the basic driving force.

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The performance of a wetland system in treating lead (Pb)/zinc (Zn) mine drainage was evaluated by using the polyurethane foam unit (PFU) microbial community (method), which has been adopted by China as a standardized procedure for monitoring water quality. The wetland system consisted of four cells with three dominant plants: Typha latifolia, Phragmites australis and Paspalum distichum. Physicochemical characteristics [pH, EC, content of total suspended solid (TSS) and metals (Pb, Zn, Cd, and Cu)] and PFU microbial community in water samples had been investigated from seven sampling sites. The results indicated that the concentrations of Pb, Zn, Cd, Cu, and TSS in the mine drainage were gradually reduced from the inlet to the outlet of the wetland system and 99%, 98%, 75%, 83%, and 68% of these metals and TSS respectively, had been reduced in concentration after the drainage passed through the wetland system. A total of 105 protozoan species were identified, the number of protozoa species and the diversity index (DI) gradually increased, while the heterotrophic index (HI) gradually decreased from the inlet to the outlet of the wetland system. The results indicated that DI, HI, and total number species of protozoa could be used as biological indicators indicating the improvement of water quality.

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The evaluation of the interfacial adhesion of coating system has always been a rough task. In this paper, a special testing method of cross-sectional indentation is applied on a model coating system, i.e. electroplated chromium on a steel substrate which is generally regarded as an example of materials pair with strong adhesion. Based on fractography analysis with SEM and interfacial stress simulation with FEM, it is found that interfacial shear stress may induce coating spalling. More interestingly, spalling location is sensitive to substrate pretreatment process. This shows the feasibility of cross-sectional indentation to distinguish interfacial strength at a high level.

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Previous studies have shown that gonads were the second target organ of microcystins (MCs), and that MCs exposure exerted obvious toxic effects on male reproductive system of mammals. However, relevant molecular evidences are still lacking. Fas-signaling pathway plays a key role in toxicant-induced germ cell apoptosis. This study was to evaluate the responses of Fas/FasL system related genes and proteins in testes of rats injected intravenously with MCs. Enhanced apoptosis of germ cells in the testes of MCs-treated rats was detected by the terminal deoxynucleotidyl transferase-mediated deoxy-UTP nick end labeling (TUNEL) associated with up-regulation of the Fas/FasL system. Both Fas and FasL protein expression were induced evidently from I h post-injection, and this high expression level maintained throughout the experiment. In addition, the activation of caspase-8 and caspase-3 protein was also observed, which were indicators of apoptosis. These results suggested the likely involvement of Fas/FasL system in the MCs-induced germ cell apoptosis. It is also suggested that MCs can cause damage to Sertoli cells directly. (C) 2009 Elsevier Ltd. All rights reserved.

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Assessment method for ecological condition of Xiangxi River system was studied by using 13 candidate metrics of epilithic diatom which can reflect conditions in pH, salinity, nitrogen uptake metabolism, oxygen requirements, saprobity, trophic state, morphological character and pollution tolerant capability etc. By one-way ANOVA, the metrics of relative abundance of acidobiontic algae (ACID), freshwater algae (FRESH), high oxygen requirement (HIGH-O), eutraphentic state (EUTRA) and mobile taxa ( MOBILE) were suitable for distinguishing sites in different conditions. Then, the river diatom index (RDI) composed of these five metrics was used to evaluate ecological condition of the river. The results showed that the healthiest sites were in the Guanmenshan Natural Reserve ( with the mean RDI of 79.73). The sites located in tributary of Jiuchong River also owned excellent state (mean RDI of 78.25). Mean RDI of another tributary - Gufu River and the main river were 70.85 and 68.45 respectively, and the unhealthiest tributary was Gaolan River (with mean RDI of 65.64). The mean RDI for all the 51 sites was 71.40. The competence of RDI was discussed with comparison of evaluation results of DAIpo and TDI, it can be concluded that multimetrics is more competent in assessment task.

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Protozoan were collected from 16 stations in water system of Changde City (China) using the PFU method. Sampling programs were conduced on a yearly basis, with seasonal frequency at diverse sites in the water system and 488 species of protozoa was identified. At the same time, Water sampling from these stations was conducted and various water chemical parameters, including DO, COD, BOD5, NH3, TP, and Volatile Phenol, were analyzed. The aim of the research was, on one hand, using chemical method to take an investigation to the water pollution status of Changde City; on the other hand, using protozoan to make an evaluation to the water quality. With the chemical water parameters and protozoa data, a biotic index was derived for the investigated region. The species pollution value (SPV) of 469 protozoa species was established, and the community pollution value (CPV) calculated from SPV was used to evaluate water quality. The method of the biotic index was tested and the result showed that CPV calculated from SPV had a close correlation with the degree of water pollution (p < 0.00001). This indicated that the method of the biotic index is reliable. The water quality degrees divided by CPV were suggested. (c) 2004 Elsevier B.V. All rights reserved.

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The spatial pattern of epilithic algae in the Xiangxi River system was studied in relation to several environmental factors by two-way indictor species analysis (TWINSPAN), detrended correspondence analysis (DCA), and canonical correspondence analysis (CCA). Eighty-nine taxa including diatoms, green algae, and blue-green algae were observed. Diatoms were dominant, and Cocconeis placentula, Cymbella minuta, Diatoma vulgare, and Gomphonema angustatum appeared in most of sampling sites. By TWINSPAN and DCA, thirty-one sites were divided into three groups based on composition and relative richness of benthic algae. CCA indicated that SiO2, pH, total phosphorus, Ca2+, velocity, elevation, and Cl- were significant environmental factors affecting the distribution of algae communities. In this minimal subset, SiO2 and pH were the most influential variables.

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In speaker-independent speech recognition, the disadvantage of the most diffused technology (HMMs, or Hidden Markov models) is not only the need of many more training samples, but also long train time requirement. This paper describes the use of Biomimetic pattern recognition (BPR) in recognizing some mandarin continuous speech in a speaker-independent manner. A speech database was developed for the course of study. The vocabulary of the database consists of 15 Chinese dish's names, the length of each name is 4 Chinese words. Neural networks (NNs) based on Multi-weight neuron (MWN) model are used to train and recognize the speech sounds. The number of MWN was investigated to achieve the optimal performance of the NNs-based BPR. This system, which is based on BPR and can carry out real time recognition reaches a recognition rate of 98.14% for the first option and 99.81% for the first two options to the persons from different provinces of China speaking common Chinese speech. Experiments were also carried on to evaluate Continuous density hidden Markov models (CDHMM), Dynamic time warping (DTW) and BPR for speech recognition. The Experiment results show that BPR outperforms CDHMM and DTW especially in the cases of samples of a finite size.

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从生态经济系统分析角度出发,对小流域生态经济结构及其演变进行分析,以期评价小流域生态经济效益。对比分析了小流域生态经济系统土地利用结构及其适宜性、产业结构、消耗结构和饲料生产平衡,利用线性模型对土地利用结构进行了优化模拟,采用描述生态系统稳定性的多样性指数描述流域经济系统稳定性,并用静态和动态模型对治理经济效果进行评价。流域农、林、牧用地比例由1990年的6.2:2.0:1.0变为2003年的1.9:1.4:1.0;农业产值所占比重由79.6%下降为54.8%;林业、牧业、副业产值比例分别由9.6%、9.6%、1.1%上升为22.7%、 15.1%、7.4%。收入多样性指数呈增加趋势,消耗结构趋向合理,饲料供需平衡,经济评价中各指标均显示经济效益显著,表明生态经济结构明显有利于生态经济系统的进展演变,流域生态经济结构趋于稳定,生态经济效益显著。

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Decision tree classification algorithms have significant potential for land cover mapping problems and have not been tested in detail by the remote sensing community relative to more conventional pattern recognition techniques such as maximum likelihood classification. In this paper, we present several types of decision tree classification algorithms arid evaluate them on three different remote sensing data sets. The decision tree classification algorithms tested include an univariate decision tree, a multivariate decision tree, and a hybrid decision tree capable of including several different types of classification algorithms within a single decision tree structure. Classification accuracies produced by each of these decision tree algorithms are compared with both maximum likelihood and linear discriminant function classifiers. Results from this analysis show that the decision tree algorithms consistently outperform the maximum likelihood and linear discriminant function classifiers in regard to classf — cation accuracy. In particular, the hybrid tree consistently produced the highest classification accuracies for the data sets tested. More generally, the results from this work show that decision trees have several advantages for remote sensing applications by virtue of their relatively simple, explicit, and intuitive classification structure. Further, decision tree algorithms are strictly nonparametric and, therefore, make no assumptions regarding the distribution of input data, and are flexible and robust with respect to nonlinear and noisy relations among input features and class labels.

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通过对渭北黄土高原地区沟坡地土壤理化性质的分析和对当地社会经济状况的调查研究,应用层次分析法对沟坡地上地自然生产力和现实生产力进行了分析和评价。在分析过程中,把当地主要造林树种根系垂直分布特征及其根系抗旱性特性纳入了分析评价体系。结果表明,嘴头村和西坡村不同树种沟坡地上刺槐(Robinia pseudoacacia)的自然生产力属于中等稍微偏上水平,而山杏(Prunus armeniacia var.ansu)、油松(Pinus tabulaeformis)和侧柏(Platycladus orientalis)的自然生产力水平则较低。两地沟坡地上的现实生产力计算结果则证明刺槐和山杏两个树种表现出了较高的水平,具有较好的发展前途;而油松和侧柏的现实生产力水平则较低,其发展推广受到了限制。群众对沟坡开发治理的态度和对开发方案的认可对沟坡开发的成功起到了重要作用。

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Land-use change is an important aspect of global environment change. It is, in a sense, the direct result of human activities influencing our physical environment. Supported by the dynamic serving system of national resources, including both the environment database and GIS technology, this paper analyzed the land-use change in northeastern China in the past ten years (1990 - 2000). It divides northeastern China into five land-use zones based on the dynamic degree (DD) of land-use: woodland/grassland - arable land conversion zone, dry land - paddy field conversion zone, urban expansion zone, interlocked zone of farming and pasturing, and reclamation and abandoned zone. In the past ten years, land-use change of northeastern China can be generalized as follows: increase of cropland area was obvious, paddy field and dry land increased by 74. 9 and 276. 0 thousand ha respectively; urban area expanded rapidly, area of town and rural residence increased by 76. 8 thousand ha; area of forest and grassland decreased sharply with the amount of 1399. 0 and 1521. 3 thousand ha respectively; area of water body and unused land increased by 148. 4 and 513. 9 thousand ha respectively. Besides a comprehensive analysis of the spatial patterns of land use, this paper also discusses the driving forces in each land-use dynamic zones. The study shows that some key biophysical factors affect conspicuously the conversion of different land- use types. In this paper, the relationships between land- use conversion and DEM, accnmlated temperature(>= 10 degrees C) and precipitation were analysed and represented. We conclude that the land- use changes in northeast China resulted from the change of macro social and economic factors and local physical elements. Rapid population growth and management changes, in some sense, can explain the shaping of woodland/grassland - cropland conversion zone. The conversion from dry land to paddy field in the dry land - paddy field conversion zone, apart from the physical elements change promoting the expansion of paddy field, results from two reasons: one is that the implementation of market-economy in China has given farmers the right to decide what they plant and how they plant their crops, the other factor is originated partially from the change of dietary habit with the social and economic development. The conversion from paddy field to dry land is caused primarily by the shortfall of irrigation water, which in turn is caused by poor water allocation managed by local governments. The shaping of the reclamation and abandoned zone is partially due to the lack of environment protection consciousness among pioneer settlers. The reason for the conversion from grassland to cropland is the relatively higher profits of fanning than that of pasturing in the interlocked zone of farming and pasturing. In northeastern China, the rapid expansion of built-up areas results from two factors: the first is its small number of towns; the second comes from the huge potential for expansion of existing towns and cities. It is noticeable that urban expansion in the northeastern China is characterized by gentle topographic relief and low population density. Physiognomy, transportation and economy exert great influences on the urban expansion.