30年来象山港海岸带土地开发利用强度时空变化研究

1 Introduction

Land use change is an important component of global changes and the research hotspot in International Geosphere-Biosphere Programme (IGBP)[1].Due to convenient transportation and rich resources,coastal zone has the highestsocial economic development and population density around the world[2].It is one of regions witnessing the most dramatic land use changes and the highest intensity.Land use changes in coastal zones have become one of the research hotspots in Land-Ocean Interactions in the Coastal Zone (LOICZ).Abundant research fruits have been achieved,mainly involving coastal land use information extraction[3,4],coastal land use characteristics[5,6],coastal land use/cover changes (LUCC)[7,8],spatial structural evolvement and driving mechanism of coastal land use[9-11],coastal land resource management[12],etc.However,there are rare researches on the land exploitation and utilization intensity of the coastal zone in the bay area[13],which is difficult to meet the needs of the sustainable utilization of coastal land resources in bay area.In this paper,spatial-temporal characteristics of coastal land use intensity in the Xiangshan Bay which develops a long history in Zhejiang Province[14]were analyzed,aiming at providing scientific references for prediction of land use changes and optimize land use structure in bay area.

2 Study area

The Xiangshan Bay lies in the southeast coastal zone of Ningbo City,Zhejiang Province(29°24′-30°07′N,121°43′-122°23′E).It covers five counties(cities and districts),including Xiangshan,Ninghai,Fenghua,Yinzhou and Beilun.The Xiangshan Bay is next to the Hangzhou Bay in the north,neighbors with the Sanmen Bay in the south,and adjoins to Zhoushan Islands in the east.It is a narrow tidal bay in the NE-SW direction.There are three secondary tidal channels in the tidal channel,namely,Xilu Harbour,Tie Harbour and Huangdun Harbour.The Xiangshan Bay covers a total length of about 60 km and 5~6 km wide in most regions.The average water depth is 10 m.There are considerable rivers flowing into the Xiangshan Bay,with a total water area of 630 km2[15].The average annual precipitation is about 1 500 mm.There are 95 rivers flowing into the bay and the average annual runoff is 12.9×108m3.

The coastal zone in the Xiangshan Bay in this paper refers to the land area with surface water flowing into the bay in surrounding Xiangshan,Ninghai,Fenghua,Yinzhou and Beilun[16](Fig.1).The study area in coastal zone in the Xiangshan Bay was determined by ASRTER GDEM V2 with a level precision of 30 m and the boundary data of the Xiangshan Bay watershed in 2015.It covers an area of 1 476 km2,excluding sea area in the bay(Fig.1).Considering obvious sea reclamation and sedimentation in the Xiangshan Bay[17],the coastal zone in the Xiangshan Bay determined according to boundaries in 2015 covers some nearshore areas in 1985,1995,and 2005.

Fig.1 The geographical location of the study area

3 Data sources and research methods

3.1 Data source and processing

TM and OLI images (spatial resolution=30 m)of the Xiangshan Bay in 1985,1995,2005,and 2015 were used as the basic remote sensing data.Each period included two scene images of 118-39#pathway and 118-40#pathway.Other research data also include 1:50 000 topographic map of the Xiangshan Bay.

In this paper,preprocessing of remote sensing data was accomplished by ENVI4.7,including atmospheric correction,geometric correction,false color composite (FCC)and image stitching[18].Then,image data of the study area were acquired by using the 2015 Xiangshan Bay watershed image cutting.Next,land use data of the study area in four periods were collected by visual interpretation and man-machine interaction interpretation of remote-sensing imagesby ENVI4.7.To ensurethe interpretation accuracy,200 checkpoints were generated in each vector diagram and the test accuracy was over 0.87 for all images,which meets the research requirement.Land use types were classified according to China’s common land classification standard and practical situations in the study area.A total of 8 land use types were classified:construction land,aquaculture land and salt pan,unused land,farmland,rivers and lakes,forest,waters and intertidal zone(Fig.2).

Fig.2 Multi period current land use map in coastal zone of the Xiangshan Bay

3.2 Research methods

Spatial-temporal changes of coastal land use changes in the Xiangshan Bay in the past three decades were analyzed by land use quantity dynamic model,land use change model,land use structure model and land use intensity model.

2.运用问题情境教学，提升学生的自主学习能力。教师可充分抓住教材中简单易懂的概念和定义，直观、具体的图片、资料及STSE问题等设置问题情境，调动学生热情参与，变“要我学”为“我要学”，使学生摆脱对教师的依赖。如教学“原子的构成”时，教师可设置问题让学生自主学习：（1）原子由几部分构成？分别是什么？（2）原子核由哪些粒子构成？这些粒子有哪些相同点和不同点？（3）原子核居于原子中心，它的体积如何？占据很大空间吗？（4）原子核和核外电子都带电，那么整个原子也带电吗？为什么？

The land use quantity dynamic model includessingle land use dynamicsand comprehensive land use dynamics.The former one discusses area changes and annual change rate of different land use types.It can describe total area changes,change trend and structural change trend of different land use types in the study period[19].Please refer to the references Liu Jiyuan et al[20]and Wang Siyuan et al[21]for more details.The later one can depict utility of land use changes in the region.It can be used to study comprehensive quantity changes of land use types in the study area in a certain period and is one shortcut to analyze and describe hot region.Details are introduced in the reference Liu Yanfang[22].

The land use change model can reflect mutual transformation relationship between the land types of the study period.It not only has detailed static area data of different land use types,but also impliesdynamic changes[23],which are conducive to comprehend causes of area changes.

The land use structure model contains information entropy and balance degree.Information entropy can measure and assess degree of order of land system[24].In this paper,the information entropy model of land use structure was defined by the Shannon formula[25].Balance degree is an improved index to represent structure of land system[26].

The land use intensity mainly reflects breadth and depth of land use.It shows not only natural attributes of land resources,but also collaborative effects of human factors and natural environmental factors[27].Based on the comprehensive analysis method of land use intensity proposed by Liu Jiyuan et al[28],land use intensity was divided into several levels according to natural balance state of natural land complex under influences of social factors and leveling indexes were given.On this basis,quantitative expressions of the integrated land use intensity index and land use intensity model were proposed[29].

In this paper,land use intensities of 8 types were determined according to classification standard of Zhuang Dafang et al[30]and practical conditions,getting 5 levels of land use intensity.The ideal land use classification is shown in Tab.1,which is slightly different with practical conditions.In practice,different land use types make contributions to regional development according to related weights[31].However,the land use intensity mode is still applicable in theoretical analysis.

Tab.1 The classification values of land use intensity

Types Waters Unused land Agricultural land Urban residential land Landuse types Waters,Rivers and lakes Intertidal zone Forest land Farmland,Aquaculture land and salt pan Construction land Unused land,Grading index 1 2 3 4 5

4 Results and analysis

4.1 Analysis of land use changes

4.1.1 Total area changes

Areas of different land use types in the Xiangshan Bay changed significantly from 1985 to 2015 (Tab.2).Viewed from the total area changes,construction land and aquaculture land and salt pan expanded significantly by 99.49%and 310.48%respectively at the end of study period.Area of unused land increased only by 45.65%.On the contrary,areas of farmland,forest and intertidal zone decreased year by year.The intertidal zone shrank the mostly (56.19%),followed by farmland (25.22%).The area of waters increased firstly and then decreased.During the study periods,the construction land expanded dramatically.Area of construction land increased by 35.375 9 km2,20.538 1 km2 and 18.9540 km2,respectively.The growth rate declined continuously from 2.40%to 1.28%.Aquaculture land and salt pan also expanded greatly,accompanied with great fluctuation of the growth rate.The maximum growth rate was achieved during 1995-2005.Farmland shrank the most.The area of farmland declined by 40.651 2 km2,39.615 4 km2 and 8.209 3 km2,respectively.The annual change rate declined continuously and reached the minimum level(0.56%)during 2005-2015.

Tab.2 Area and it’s changes of land use types of the Xiangshan Bay coastal zone in each year and each stage(km2)

Landuse types Statistics 1985 1995 2005 2015 1985-1995 1995-2005 2005-2015 Construction land Area/km2 075.253 6 110.629 5 131.167 6 150.121 6 -35.375 9 -20.538 1 -18.954 0 Proportion/% 005.10 007.49 008.89 010.17 0-2.40 0-1.39 -01.28 Aquaculture land and salt pan Area/km2 011.516 5 021.493 9 047.215 3 047.272 9 0-9.977 4 -25.721 4 -00.057 6 Proportion/% 000.78 001.46 003.20 003.20 0-0.68 0-1.74 -00.00 Unused land Area/km2 006.960 7 008.015 2 009.332 9 010.138 3 -01.054 5 0-1.317 7 -00.805 4 Proportion/% 000.47 000.54 000.63 000.69 0-0.07 0-0.09 -00.05 Farmland Area/km2 350.759 5 310.108 3 270.492 9 262.283 6 -40.651 2 -39.615 4 0-8.209 3 Proportion/% 023.76 021.01 018.32 017.77 0-2.75 0-2.68 0-0.56 Rivers and lakes Area/km2 020.705 2 022.878 0 021.325 8 020.804 1 02.172 8 0-1.552 2 0-0.521 7 Proportion/% 001.40 001.55 001.44 001.41 00.15 0-0.11 0-0.04 Forest land Area/km2 995.383 6 991.296 3 988.711 5 978.968 1 0-4.087 3 0-2.584 8 0-9.743 4 Proportion/% 067.43 067.15 066.98 066.32 0-0.28 0-0.18 0-0.66 Waters Area/km2 000.605 9 000.3371 000.245 4 000 0-0.268 8 0-0.091 7 0-0.245 4 Proportion/% 000.04 000.02 000.02 000 0-0.02 0-0.01 0-0.02 Intertidal zone Area/km2 014.955 5 011.382 2 007.649 1 006.551 9 0-3.573 3 0-3.733 1 0-1.097 2 Proportion/% 001.01 000.77 000.52 000.44 0-0.24 0-0.25 0-0.07

4.2.3 Comprehensive land use dynamics

采用人工材料治理河床而忽略河流自然属性的河流治理方法已被各国逐渐淘汰[14]，而生态河堤已成为国际上堤坝建设新的焦点问题。

The area transfer matrixesof 8 land use typesin three periods(1985-1995,1995-2005 and 2005-2015)in the coastalzone of the Xiangshan Bay were analyzed(Tab.3,Tab.4 and Tab.5).Mutual transformation of different land use types in the coastal zone of the Xiangshan Bay in the past three decades have some characteristics: (a)The construction land expanded significantly,which were transformed from farmland,aquaculture land and salt pan and forest.Among them,farmland occupied the highest proportion.With the progressing of urbanization,demands for construction land increased dramatically.(b)Aquaculture land and salt pan also expanded greatly,only next to the construction land.It presented the highest annual change rate in 30 years and was mainly transformed from farmland,followed by intertidal zone.(c)Farmland shrank the mostly.It was mainly transformed into construction land,aquaculture land and salt pan,and forest.Most of reduced farmland resources were changed into construction land.Transformation from farmland to construction land is non-agriculturization of farmland and the inevitable consequence of urbanization.Transformation from farmland into aquaculture land and salt pan was mainly driven by economic benefits.Transformation from farmland into forest land was mainly driven by government’s compulsory policies,such as return farmland to forests.(d)Forest shrank the second.It mainly transformed into farmland and construction land.The transformation of forest land into farmland is mainly the consequence of long-distance displacement for cultivated land requisition-compensation balance.

Tab.3 The transfer matrix of eight land use types of the Xiangshan Bay coastal zone during 1985-1995(km2)

("-"means that there is no conversion between the two types of land,the same as below)

Construction land Aquaculture land and salt pan Unused land FarmlandRivers and lakes Forest land WatersIntertidal zone Total Construction land072.472 900.002 30.703 5 001.287 400.067 0000.651 6— 00.068 9 0 075.253 6 Aquaculture land and salt pan 000.086 109.562 40.017 9 001.547 900.034 7000.141 3— 00.126 2 0 011.516 5 Unused land 000.396 4 — 6.183 3 000.136 500.236 1000.001 2—00.007 2 0 006.960 7 Farmland 035.121 608.600 40.282 9 296.253 201.538 1008.437 0— 00.526 3 0 350.759 5 Rivers and lakes000.298 700.388 70.112 8 000.362 319.322 6000.213 2— 00.006 9 0 020.705 2 Forest land 002.027 700.029 20.435 8 009.897 201.500 6981.461 4— 00.031 7 0 995.383 6 Waters —00.044 2— — —000.002 4 0.337 1 00.222 2 0 000.605 9 Intertidal zone 000.226 102.866 70.279 0 000.623 800.178 9000.388 2— 10.392 8 0 014.955 5 Total 110.629 5 21.493 9 8.015 2 310.108 3 22.878 0 991.296 3 0.337 1 11.382 2 1 476.140 5

Tab.4 The transfer matrix of eight land use types of the Xiangshan Bay coastal zone during 1995-2005(km2)

Construction land Aquaculture land and salt pan Unused land FarmlandRivers and lakes Forest land WatersIntertidal zone Total Construction land103.132 600.313 30.286 7 005.475 400.219 5001.149 5— 0.052 50 110.629 5 Aquaculture land and salt pan 003.275 215.749 30.371 1 001.412 500.114 0000.171 9— 0.399 90 021.493 9 Unused land 000.211 300.891 36.356 5 000.037 600.112 8000.391 4— 0.014 300 08.015 2 Farmland 021.250 325.523 61.325 4 254.370 000.381 5007.137 4— 0.120 10 310.108 3 Rivers and lakes000.392 300.496 70.219 8 000.601 920.131 1000.896 6— 0.139 60 022.878 0 Forest land 002.384 700.551 40.610 2 008.307 900.364 1978.932 2— 0.145 80 991.296 3 Waters 000.011 800.007 00.026 9 000.026 2— —0.245 40.019 800 00.337 1 Intertidal zone000.509 403.682 70.136 3 000.261 400.002 8000.032 5— 6.757 100 11.382 2 Total 131.167 6 47.215 3 9.332 9 270.492 9 21.325 8 988.711 5 0.245 4 7.649 1 1 476.140 5

Tab.5 The transfer matrix of eight land use types of the Xiangshan Bay coastal zone during 2005-2015(km2）

Construction land Aquaculture land and salt pan Unused land Farmland Rivers and lakes Forest land WatersIntertidal zone Total Construction land125.734 503.485 500.293 4 000.712 600.240 9 000.653 1— 0.047 60 131.167 6 Aquaculture land and salt pan 005.935 036.390 101.309 5 002.472 000.055 7 000.159 2— 0.893 80 047.215 3 Unused land 000.958 701.105 006.811 3 000.426 6— 000.028 6—0.002 70 009.332 9 Farmland 014.072 804.317 100.337 2 249.662 000.367 3 001.639 8— 0.096 70 270.492 9 Rivers and lakes000.167 300.755 700.112 6 000.283 019.504 2 000.498 8— 0.004 20 021.325 8 Forest land 002.543 300.061 300.857 3 008.640 600.625 9 975.968 5— 0.014 60 988.711 5 Waters 000.061 1— — —00.184 30 000.245 4 Intertidal zone000.648 901.158 200.417 0 000.086 800.010 1 000.020 1— 5.308 00 007.649 1 Total 150.121 6 47.272 9 10.138 3 262.283 6 20.804 1 978.968 1 0 6.551 9 1 476.140 5

4.2 Analysis of land use structure and dynamics

4.2.1 Information entropy

It can be seen from Tab.6 that information entropy and balance degree of land use structure in coastal region of the Xiangshan Bay increased continuously throughout the study period.Structure and orderness of the land system were deteriorating and the area difference among different land use types was narrowing.The minimum information entropy(0.931 6)was in 1985,but the orderness of coastal land structure was relatively high,accompanied with strong system stability,low area distribution uniformity of different land use types,and small interference from human activities.The information entropy increased by 0.051 7 from 1985 to 1995,indicating the great area difference among different land use types.At the same time,the balance degree of land system increased by 0.024 9,indicating the slow reduction of orderness of land structure.From 1995 to 2005,the information entropy increased slightly,indicating the slow weakening of stability of land system.The minimum growth of information entropy(0.013 7)was achieved from 2005 to 2015.However,information entropy reached the peak (1.040 3).This reflected that with continuous development of coastal zone,land structure in the study areabecame increasingly vulnerable,manifested by increasing orderness of different land use types and complexity of land utilization.

Tab.6 Land use structure information entropy,equilibrium degree and dominance of the Xiangshan Bay coastal zone in 1985,1995,2005,2015

Time Information entropy Equilibrium degree Dominance 1985 0.931 6 0.448 0 0.552 0 1995 0.983 3 0.472 9 0.527 1 2005 1.026 6 0.493 7 0.506 3 2015 1.040 3 0.500 3 0.499 7

4）教学实施，主要采取引导学生自主探究、组织研讨和教师答疑的方式。在课程单元教学中要着重考虑以下几个方面。

The comprehensive land use dynamics in the study area during 1985-1995,1995-2005 and 2005-2015 were calculated 0.27%,0.31%and 0.19%,showing an inverted V-shaped variation with time.Mutual transformation among different land use types was fluctuating continuously.The highest comprehensive land use dynamics was achieved during 1995-2005,indicating the great mutual conversion between land use typesand quick land use changes in the study area.The comprehensive land use dynamics during 2005-2015 was the smallest,which reflected stable land use changes and small area conversion in the study area.

(2)By analyzing status maps of land use intensity (Fig.4),land use intensity in coastal zone of the Xiangshan Bay was affected by local geomorphology significantly.Land use intensity of low mountainous and hilly lands was high,which was attributed to the relatively flat terrain,convenient transportation and easy utilization.Land use intensity of coastal zone is relatively high,which is related with the rich resource reserves,intense human activities and the environmental conditions.Influences of administration centers at different levels on land use intensity in coastal zone of the Xiangshan Bay shouldn’t be overlooked.Surrounding areas of Ninghai County showed the highest land use intensity in the whole Xiangshan Bay region,which was related with the advantageous geological conditions.Human economic activities and land use in coastal zone are closely related.They promote mutually,thus increasing land use intensity as time went by.High intensity and medium high intensity land resources were mainly in county or village administrative centers with high population density and big demands for land resources.Land use intensity in coastal zone was kept at a relatively high level.

Fig.3 Dynamic degree of single land use type in four periods of 1985-1995,1995-2005,2005-2015 and 1985-2015

4.1.2 Mutual transformation of different land use types

In Fig.3,aquaculture land and salt pan presented the highest annual change rate(10.35%)in the past three decades,followed by construction land (3.32%).The annual change rates of waters,unused land and intertidal zone were relatively high,while annual change rates of rest land use types were relatively small.During 1985 to 1995,the annual change rate of aquaculture land and salt pan (8.66%)was far higher than those of other land use types.The annual changes rates of construction land (4.70%)and waters(4.44%)were equivalent.Intertidal zone (2.39%)also showed high annual change rate.During 1995 to 2005,the annual change rates of all land use types fluctuated more violently compared to those in the rest two periods.They were mainly close to the maximum values.For example,the annual change rate of aquaculture land and salt pan was 11.97%,which was the highest in all three periods.During 2005 to 2015,the annual change rates of different land use types were basically equivalent.

4.3 Analysis of spatial-temporal changes of land use intensity

Land use intensity indexes in 1985,1995,2005 and 2015 were calculated by the land use intensity model.Land use types were graded according to land use intensity.Statistics on proportions of different levels were made (Tab.7).The status maps of land use intensity(Fig.4)and land use intensity changes(Fig.5)of the study area in different periods were obtained by using ArcGIS10.2 according to intensity grading,integrated land use index and land use intensity change model.Data and maps were combined to better analyze spatial-temporal changes of land use intensity in coastal zone of the Xiangshan Bay.

为了更好地评测本文算法提出的框架的性能，构建一个与本文算法框架具有相同网络层数的CNN框架进行对比。在网络的前4个卷积层，对比框架与本文算法框架具有相同的卷积核尺寸和数量；为了对比不同结构作为网络输出层的效果，对比框架的输出层设置为全连接层。两个CNN框架具体参数如表4所示，其中CNN-1为本文算法的框架，CNN-2为对比框架，加粗数字指网络中的训练参数。

逆境中，汤甲真先后两次被派遣到湘西山区沅陵县和凤凰县苗族聚居区做农村基层工作。其间，得到有关领导的关注。1974年秋，汤甲真调入当时正在建设的巴陵石化原洞庭氮肥厂工作。

To sum up,coastal zone of the Xiangshan Bay witnesses the rapid development of all land use types from 1985 to 1995,which was further accelerated during 1995-2005.Annualchange rates ofdifferentland use types fluctuated violently.However,development of different land use types slowed down during 2005 to 2015.

2.1 年龄、病程、月经及生育 目前研究证实 ,年龄是EAOC的主要危险因素。一项根据台湾NHIRD数据库的研究结果显示，EAOC的IR随年龄的增长而增加，<30岁女性的IR为4.99/万。30～50岁女性的IR为35.81/万[4]。关于病程的影响尚无定论，普遍认为病程长恶变率高，但一项对台湾人群的研究表明，EAOC的发生不受子宫内膜异位症暴露时间的影响[5]。月经周期短、初潮早、绝经晚、孕产次低等因素可使经血逆流盆腔、排卵次数及上皮损伤概率提高，从而增加了子宫内膜异位症发生率，并且增加其恶变率。

(3)Viewed from the variation of integrated land use index with time (Fig.5),the integrated land use index in the study area have positives and negatives in the past 3 decades.Land area with positive integrated land use index reached as high as 19.83%,indicating the active land use activities in coastal zone of the Xiangshan Bay.With the improvement of urbanization and the expansion of counties,the surrounding land resources of counties and districts were developed and utilization,and utilization degree of the original urban area was strengthened.The proportion of developing land area during 1985-1995,1995-2005 and 2005-2015 were 12.87%,10.43%and 9.71%,respectively.About 10%land use entered into the development period during each study period.Although proportion of developing land area was different in different periods,the land use intensity increased in-depth in all study periods.This was closely related frequent human interferences to land use in coastal regions.Economic benefit was the most direct driving factor of such changes.Regional development’s dependence on land resources becomes extremely significant.

To sum up,land use intensity in coastal zone of the Xiangshan Bay was increasing stage by stage,especially in surround areas of counties and districts.This reflects the rapid urbanization in the Xiangshan Bay.Land use intensity around villages and towns was relatively high,which was attributed to the big demands for construction land.The area difference among different land use types in the study area was narrowing gradually,while stability of land use structure increased continuously,showing a promising development prospect.

(1)Based on statistics of integrated land use index in different periods (Tab.7),the land use intensity in 1985 was above the average.The proportion of medium intensity and higher land resources was 44.16%.The medium high intensity land resources accounted the highest proportion(20.58%)of total land resources,followed by medium intensity land resources (19.60%).In 1995,the proportion of high intensityland resources increased significantly by 2.23%compared to that in 1985.The growth rate was the highest in all study period,reaching 56.03%.Proportions of other levels decreased to different extents,especially the medium intensity land resources.The overall land use intensity in 1995 was slightly lower than that in 1985,but was still above the average level.In 2005,proportion of the high intensity land resources was still increasing continuously.The proportion increased by 1.84%.The proportion of medium intensity land resources increased slightly,whereas the proportions of the rest levels decreased.However,reductions slowed down compared to those in 1995.The proportion of high intensity land resources was increased by 1.20%in 2015,achieving a growth rate of 14.91%.Proportions of medium high intensity and medium intensity land resources were 0.16%and 0.15%higher than those in 2005 and 1995.

4.2.2 Single land use dynamics

Tab.7 The intensity level division,area and proportion of each period

Range of valuesProportion/%100-250 low 36.605 4 2.48 034.591 5 2.34 027.542 9 01.87 027.839 1 01.89 250-316 medium low 787.964 1 53.37 775.170 0 52.50 770.076 0 52.15 747.390 1 50.62 316-362 medium 289.407 8 19.60 275.962 2 18.69 276.909 9 18.75 279.101 5 18.90 362-416 medium high 303.801 2 20.58 299.181 1 20.26 283.188 5 19.18 285.557 8 19.34 416-500 high 58.758 2 3.98 091.632 0 6.21 118.819 5 08.05 136.648 4 09.25 Intensity levels 1985 1995 2005 2015 Area/km2 Proportion/%Area/km2 Proportion/%Area/km2 Proportion/%Area/km2

Fig.4 Comprehensive index of land use intensity in the four periods of Xiangshan Bay in 1985,1995,2005,and 2015

Fig.5 The variation of integrated land use index in the whole period and sub period

5 Conclusions

(1)Areas of different land use types in the coastal zone of the Xiangshan Bay changed significantly from 1985 to 2015.Area of construction land increased significantly by 74.868 0 km2,showing a change rate of 99.48%.Farmland decreased the most by 88.475 9 km2,showing a change rate of 25.22%.Aquaculture land and salt panachieved the highest growth rate(310.48%).Intertidal zone suffered the fastest reduction and the change rate was 56.19%.Area of construction land in all three periods(1985-1995,1995-2005 and 2005-2015)increased significantly.Significant area changes of aquaculture land and salt pan and farmland were only observed in the first two periods.

(2)In the study area,farmland was transformed into construction land,and forest was transformed into farmland.The transformation area of these four land use types was decreasing gradually.During 1985-1995,1995-2005 and 2005-2015,the transformation areas from farmland into construction land were 35.121 6 km2,21.250 3 km2and 14.072 8 km2,respectively.The transformation areas from forestinto farmland were 9.897 2 km2,8.307 9 km2 and 8.640 6 km2.The transformation among different land use types was decreasing gradually,indicating that the development and utilization was becoming more and more coordinated.

(3)The information entropy and balance degree increased gradually in the 4 periods,while the difference among different land use types was narrowing.The land use structure became more and more stable.Only aquaculture land and salt pan presented high single land use dynamics,but rest land use types had general dynamic changes.The dynamic change of all land use types was the most obviousduring 1995-2005.The comprehensive land use dynamics in coastal zone of the Xiangshan Bay increased gradually,and the degree of conversion between land use types was from big to small.

(4)The land development and utilizationin coastal zone of the Xiangshan Bay was deepened and strengthened continuously.The tendency of land use structure during 1985-2015 was characterized bymedium low intensity land,accompanied with medium intensity and medium high intensity land resources.At the same time,high intensity land expanded and low intensity land narrowed.Land use in coastal zone of the Xiangshan Bay was in the development stage in all three periods (1985-1995,1995-2005 and 2005-2015).Although land use intensity was increasing gradually,there’s imbalance among different land use types and most of land use types were in the adjustment period.Therefore,further unified management and coordination were needed.Moreover,land use intensity in coastal zone of the Xiangshan Bay was affected by local geomorphology and administrative centers.These influences shall be taken into consideration in future land use planning and adjustment in order to improve coastal land use planning.

卢春泉先后在中国人民大学、中国证监会、三峡集团等单位供职并担任领导职务，对资本市场非常熟悉。2015年，卢春泉离开体制出来创业，出任普润资本总经理，管理旗下的私募基金。

Acknowledgments

记忆里，腊味萦绕在最寒冷萧条的季节，成为味蕾最后的守护者。从大雪到清明，腊味都是吃不完的。春风起时，野蒿一夜丛生。妈妈便将最后剩余的一点腊肉切成丁，煮一锅野蒿饭。野菜的清香，送走了寒冬的萧索，年年岁岁就这样延续下去，这一味，始终如初。

The study was supported by National Natural Science Foundation of China(No.41471004).

走嘞。王树林如释重负长慨一声。收了伞，钻了进去。他们有过约定，一同回家，两人就驾驶辛娜的Q Q，最初入住小区的时候，他们只办了一个车位证。

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