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24 pages, 11115 KB  
Article
Monitoring of Land Subsidence and Analysis of Impact Factors in the Tianshan North Slope Urban Agglomeration
by Xiaoqiang Yi, Lang Wang, Hui Ci, Ran Wang, Hui Yang and Zhaojin Yan
Land 2025, 14(1), 202; https://doi.org/10.3390/land14010202 - 20 Jan 2025
Cited by 2 | Viewed by 2665
Abstract
As one of the 19 key regions for comprehensive land development in China, the Tianshan North Slope urban agglomeration is significant for China’s urban development when calculating the land subsidence and analyzing the impact factors. This study focused on eight cities in the [...] Read more.
As one of the 19 key regions for comprehensive land development in China, the Tianshan North Slope urban agglomeration is significant for China’s urban development when calculating the land subsidence and analyzing the impact factors. This study focused on eight cities in the Tianshan North Slope urban agglomeration, calculating the land subsidence rate from 18 January 2018 to 12 April 2023 using Sentinel-1A data and analyzing the spatiotemporal patterns and impact factors of land subsidence. The results showed that (1) the average land subsidence rate is mainly distributed between −30 and 10 mm/a, and the maximum subsidence rate can reach −358 mm/a. Land uplift mainly occurs in Hutubi County and Manas County. (2) From the transition matrix, landscape pattern index, and Moran’s I, the spatiotemporal patterns of the land subsidence rate are obvious, with a spatial positive correlation. During the monitoring period, each administration experienced varying degrees of land subsidence or uplift processes. (3) Using GeoDetector to perform quantitative analyses, it was found that the hydrological environment is significant to land subsidence, and human activities, such as road network density and nighttime lighting, contribute the least to land subsidence, suggesting that it is related to the arid climate of the study area. This paper aims to provide theoretical support for the stable development of and production activities in the study area. This approach not only offers technical support but also provides guidance for evaluating, monitoring, and the early warning of land subsidence in the region. Full article
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26 pages, 17108 KB  
Article
Study on the Impact of Rural Tourism Construction Projects on Farmers’ Livelihood Capital and Livelihood Options
by Zexian Li, Yuejian Wang, Lei Wang, Liping Xu, Huanhuan Chen and Chenglong Yao
Agriculture 2024, 14(7), 1024; https://doi.org/10.3390/agriculture14071024 - 27 Jun 2024
Cited by 8 | Viewed by 3706
Abstract
Rural tourism is a new driving force for achieving rural revitalization and development, promoting rural economic prosperity, and serving as a new industrial approach to achieving the transformation and upgrading of farmers’ livelihoods. This paper focuses on Manas County as the research subject [...] Read more.
Rural tourism is a new driving force for achieving rural revitalization and development, promoting rural economic prosperity, and serving as a new industrial approach to achieving the transformation and upgrading of farmers’ livelihoods. This paper focuses on Manas County as the research subject and employs farmer questionnaire interviews and participatory rural appraisal methods to categorize villages into four types: “scenic area-dependent” villages, “industry-dependent” villages, “folklore-dependent” villages, and “suburban-dependent” villages. Based on the sustainable livelihood analysis framework proposed by the Department for International Development, we developed a sustainable livelihood framework for farm households in Manas County and analyzed the effects of rural tourism on farm households’ livelihood capital and livelihood strategies as the watershed of the rural tourism takes shape, taking livelihood capital and livelihood strategies as the entry point. The factors influencing the livelihood capital and livelihood options of farm households in the context of rural tourism are analyzed. The results show that: (1) The overall livelihood capital of farmers engaging in rural tourism is significantly greater than that of farmers not participating in rural tourism. Additionally, variations exist in the livelihood capital of different types of rural tourism within villages. (2) Participation in rural tourism significantly influences farmers’ choices of livelihood strategies. Compared with individuals who do not engage in rural tourism, those involved in rural tourism are more likely to opt for self-management livelihood strategies. The proportion of self-managed farmers in villages based around scenic areas is the highest. (3) The effect of rural tourism on farm households in Manas County is generally positive, and various types of villages yield different impact effects. (4) Participation in rural tourism significantly increases the possibility of farmers choosing self-management livelihood strategies, while it reduces the possibility of farmers choosing agriculture-oriented livelihood strategies. In all villages, except those dependent on industry, the decision to engage in rural tourism significantly impacts farmers’ selection of self-management livelihood strategies. Full article
(This article belongs to the Section Agricultural Economics, Policies and Rural Management)
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11 pages, 1776 KB  
Article
Effects of Different Proportions of Organic Fertilizer Replacing Chemical Fertilizer on Soil Nutrients and Fertilizer Utilization in Gray Desert Soil
by Weidan Lu, Zhiqiang Hao, Xiaolong Ma, Jianglong Gao, Xiaoqin Fan, Jianfu Guo, Jianqiang Li, Ming Lin and Yuanhang Zhou
Agronomy 2024, 14(1), 228; https://doi.org/10.3390/agronomy14010228 - 22 Jan 2024
Cited by 43 | Viewed by 9678
Abstract
Organic fertilizer can improve soil management and alleviate soil nutrient loss caused by excessive fertilization. This study determines a fertilization scheme that can achieve high and stable crop yield and effective soil fertilization by exploring the effects of different organic fertilizer proportions on [...] Read more.
Organic fertilizer can improve soil management and alleviate soil nutrient loss caused by excessive fertilization. This study determines a fertilization scheme that can achieve high and stable crop yield and effective soil fertilization by exploring the effects of different organic fertilizer proportions on soil nutrient content, fertilizer utilization rate, and wheat yield. The experiment was conducted from 2018 to 2020 using the Xinchun 38 wheat variety and gray desert soil. The experiment used six treatments: no fertilizer (CK), with normal nitrogen and phosphorus fertilizer (CF). The amount of conventional chemical nitrogen fertilizer was reduced by 6%, 12%, 18%, and 24%, respectively, and supplemented with organic nitrogen fertilizer of the same proportion. The experimental treatment codes were SF6, SF12, SF18, and SF24, respectively. Plant samples from six wheat growth stages and 0–20 cm soil samples were collected to analyze the nitrogen and phosphorus content and organic matter; dry matter accumulation, crop yield, and yield components were measured at the harvest stage. Soil available nitrogen, phosphorus, potassium, and soil organic matter contents increased with the replacement ratio of organic fertilizer after three consecutive years of application. The available nutrients and organic matter in soil treated with SF18 and SF24 were significantly higher than those in CK and CF. The dry matter accumulation and nutrient accumulation of wheat increased with increasing organic fertilizer replacement rates of SF18 and SF24, respectively. Nitrogen and phosphorus fertilizer utilization rates, partial productivity, and agricultural use efficiency also increased, with the SF18 and SF24 treatments having higher organic fertilizer replacement rates than those in the other treatments. The number of ears, 1000-grain weight, and yield of wheat treated with SF18 treatment produced the best results. Therefore, continuously using organic fertilizer as a partial replacement for conventional fertilizer can increase wheat growth and soil nutrient availability, which can improve the utilization rate of fertilizer, thereby achieving stability and even a significant increase in yield. Full article
(This article belongs to the Section Soil and Plant Nutrition)
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20 pages, 1091 KB  
Article
Geographical Detector-Based Research of Spatiotemporal Evolution and Driving Factors of Oasification and Desertification in Manas River Basin, China
by Jinmeng Lee, Xiaojun Yin, Honghui Zhu and Xin Zheng
Land 2023, 12(8), 1487; https://doi.org/10.3390/land12081487 - 27 Jul 2023
Cited by 8 | Viewed by 2149
Abstract
Oasification and desertification are two essential processes of land use and cover (LULC) change in arid regions. Compared to desertification, which is widely regarded as the most severe global ecological issue, the importance of oasification has not received universal recognition. However, neglecting oasification [...] Read more.
Oasification and desertification are two essential processes of land use and cover (LULC) change in arid regions. Compared to desertification, which is widely regarded as the most severe global ecological issue, the importance of oasification has not received universal recognition. However, neglecting oasification can lead to detrimental outcomes to the effectiveness of ecological governance by affecting the comprehensiveness of environmental policies proposed only based on desertification. Therefore, this study incorporates oasification into the examination of desertification by analyzing land use data for five representative periods spanning from 1980 to 2020, as well as socioeconomic and environmental data from 2000 to 2010. The aim is to evaluate the spatial and temporal dynamics of oasification and desertification in the Manas River Basin and identify the underlying factors driving these processes. The findings indicated that (1) the general trend of oasification and desertification exhibited the expansion of oases and the retreat of deserts. Specifically, the oasification area showed a “decrease-increase-decrease” pattern over time, while the desertification area consistently decreased. (2) In terms of spatial distribution, oasification and desertification displayed a transition from scattered and disordered patterns to an overall more organized pattern, with the hotspot area of desertification shifting from Shawan County to Manas County over time. (3) Population density, average land GDP, soil type and annual precipitation significantly influenced the degree of oasification, with driving force q-values above 0.4, which were the key factors driving oasification. Population density and average land GDP significantly affected the degree of desertification, with driving force q-values above 0.35, which were the key factors driving desertification. The driving force of all factors increased significantly after the interaction, and socioeconomic factors influenced oasification and desertification more than other factors. The study’s findings aim to provide a scientific basis for land resource use, ecological governance and sustainable development in the Manas River basin. Full article
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13 pages, 1153 KB  
Article
Potassium Determines Sugar Beets’ Yield and Sugar Content under Drip Irrigation Condition
by Xiangwen Xie, Qianqian Zhu, Yongmei Xu, Xiaopeng Ma, Feng Ding and Guangyong Li
Sustainability 2022, 14(19), 12520; https://doi.org/10.3390/su141912520 - 30 Sep 2022
Cited by 13 | Viewed by 3177
Abstract
Sugar beet is one of the main sugar crops and an important cash crop in the three northern regions of China (Northeast China, North China, and Northwest China). As an arid region, Xinjiang lacks water resources. The establishment of a reasonable drip-irrigation system [...] Read more.
Sugar beet is one of the main sugar crops and an important cash crop in the three northern regions of China (Northeast China, North China, and Northwest China). As an arid region, Xinjiang lacks water resources. The establishment of a reasonable drip-irrigation system for sugar beet in Xinjiang can not only achieve the goal of high quality and high yield, but is also crucial for the efficient utilization of water and fertilizer. This research was implemented in the experimental field of the Xinjiang Academy of Agricultural Sciences’ Sugar Beet Improvement Center in Manas County, Xinjiang, from the year 2019. Taking ST 15140 sugar beet as the experimental variety, a field study was conducted to investigate the effects of different irrigation and fertilization methods on the yield and sugar content of sugar beets. Ten treatments of two irrigation levels (W1: 4500 m3 ha−1, W2: 5400 m3 ha−1) and five fertilization methods (F1, F2, F3, F4, and F5) were carried out in a randomized block design with three replications. The yield and sugar content; growth indicators such as leaf photosynthetic rate, stomatal conductance, chlorophyll content and intercellular CO2 concentration; and fertilizer-use efficiency (nitrogen-use efficiency (NUE), phosphorus-use efficiency (PUE), and potassium-use efficiency (KUE)) during the sugar beet growing seasons were determined. The results indicated that the W1F3 (4500 m3 ha−1, N 229.5 kg ha−1 + P2O5 180 kg ha−1 + K2O 202.5 kg ha−1 + hydroquinone 229.5 g ha−1) treatment had the highest yield and sugar content of 132.20 Mg ha−1 and 15.61%, respectively. For crop growth indicators, the photosynthetic rate (33.27 μmol m−2 s−1) and the stomatal conductance (252.67 mmol m−2 s−1) under W1F3 were both the highest among all of the treatments. The fertilizer-use efficiency in W1F3 was in the following order: KUE > NUE > PUE. The highest KUE (128.10%) and NUE (65.49%) occurred under W1F3 at the sugar accumulation stage of the crop growing season. In addition, K determined the yield and sugar content of sugar beet by influencing growth factors such as the photosynthetic rate, chlorophyll content, intercellular CO2 concentration, along with the KUE, which explained 30.2%, 5.1%, 10%, and 14.7% of the variation in yield and sugar content, respectively. The results of this study indicated that the application of an inhibitor with optimized-minus-N fertilization under lower irrigation (W1F3) was the optimal treatment. Above all, K determined the yield and sugar contents of sugar beets, emphasizing the pivotal role of K in the growth, physiological processes, and output of sugar beets. Full article
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19 pages, 1195 KB  
Article
Analysis of the Difference in Changes to Farmers’ Livelihood Capital under Different Land Transfer Modes—A Case Study of Manas County, Xinjiang, China
by Difan Liu, Yuejian Wang, Yuejiao Chen, Guang Yang, Hailiang Xu and Yuxiang Ma
Land 2022, 11(8), 1369; https://doi.org/10.3390/land11081369 - 22 Aug 2022
Cited by 4 | Viewed by 2539
Abstract
Farmers’ livelihoods alter as a direct result of land transfer. This study examined the impacts of land transfer on several indicators of farmers’ livelihood capital, as well as variations in the effects of different land transfer methods on farmers’ capital, in an effort [...] Read more.
Farmers’ livelihoods alter as a direct result of land transfer. This study examined the impacts of land transfer on several indicators of farmers’ livelihood capital, as well as variations in the effects of different land transfer methods on farmers’ capital, in an effort more effectively to enhance farmers’ livelihoods. To compare the changes in farmers’ livelihood capital under four different modes—the farmers’ spontaneous model, centralized and continuous, joint-stock cooperative, and leaseback and re-contracting—this study calculated farmers’ livelihood capital index based on 600 questionnaires in accordance with the sustainable livelihood capital framework. The study’s findings indicate the following outcomes: (1) Farmers’ livelihood capital is significantly impacted favorably by land transfers. (2) Different types of farmers experienced different changes in their livelihood capital after land transfer: purely agricultural farmers’ livelihood capital value increased by 0.138, primarily due to an increase in physical capital; agricultural part-time farmers’ livelihood capital value increased by 0.105; non-agricultural part-time farmers’ livelihood capital value increased by 0.081; and non-agricultural farmers’ livelihood capital value increased by 0.081. (3) The most efficient strategy to increase livelihood capital was to use the leaseback and recontracting model with “village collective + planting leadership company” as the primary business organization. The results provide practical guidance for land transfer in Manas County, and valuable suggestions for improving farmers’ livelihoods in arid areas. Full article
(This article belongs to the Special Issue Rural Land Use in China)
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18 pages, 5186 KB  
Article
Study on the Spatial Allocation of Receding Land and Water Reduction under Water Resource Constraints in Arid Zones
by Xin Yan, Yuejian Wang, Yuejiao Chen, Guang Yang, Baofei Xia and Hailiang Xu
Agriculture 2022, 12(7), 926; https://doi.org/10.3390/agriculture12070926 - 26 Jun 2022
Cited by 3 | Viewed by 2363
Abstract
The withdrawal of cultivated land policy is not only an important task to promote cultivated land rest and alleviate the contradiction between supply and demand of water resources in arid areas, but also an important way to realize the sustainable development of agriculture [...] Read more.
The withdrawal of cultivated land policy is not only an important task to promote cultivated land rest and alleviate the contradiction between supply and demand of water resources in arid areas, but also an important way to realize the sustainable development of agriculture and social economy. This study adopted the minimum per capita area method, ESPR (Exposure-Sensitivity-Pressure-Response) vulnerability assessment model, grey prediction model, and GIS spatial analysis. Furthermore, based on the characteristics of water resource constraints in the arid zone, Manas County was used as the study area. By exploring and analyzing the area of land retreat, through identifying its occurrence and position, the spatial zoning layout of land retreat can be realized to guarantee the effective implementation of water retreat and reduction. The following points were noted from the results: (1) the upper and lower limits of the area of receding land in Manas County were measured using the minimum per capita area method and the principle of balancing water supply and demand. The receding land in Manas County measured 16,493.68–20,749.90 hm2, which accounted for 24.31–30.58% of the total area of cultivated land. (2) The results obtained from constructing the ESPR vulnerability assessment model, used to assess the vulnerability of cultivated land in Manas County, showed that the overall vulnerability of cultivated land in Manas County was high, with 94.74% of the county’s cultivated land being moderately vulnerable or worse, which necessitates the optimization of land use. (3) The area of cultivated land withdrawal under the water resource constraint was used as a constraint for the withdrawal of cultivated land. Based on the evaluation of the vulnerability of cultivated land, with the results arranged from small to large, it was concluded that the area of cultivated land withdrawal in Manas County could reach up to 16,787.34 hm2. There are four types of cultivated land withdrawals: desertified withdrawal, saline withdrawal, groundwater overexploitation withdrawal, and soil contamination withdrawal. The results of this study can provide a reference for Manas County to scientifically formulate a reasonable and orderly withdrawal system of farmland to reduce water use. Full article
(This article belongs to the Special Issue Precision Water Management in Dryland Agriculture)
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19 pages, 4803 KB  
Article
Assessment of Value Changes and Spatial Differences in Land Use Based on an Empirical Survey in the Manas River Basin
by Xin Yan, Yuejian Wang, Na Liao, Hailiang Xu and Zili Fan
Land 2021, 10(9), 961; https://doi.org/10.3390/land10090961 - 10 Sep 2021
Cited by 8 | Viewed by 2436
Abstract
Land integration is an important means of increasing the multifunctional value of arable land. The scientific measurement of the integrative value of arable land before and after land consolidation can improve farmers’ overall understanding of the value of arable land, increase their awareness [...] Read more.
Land integration is an important means of increasing the multifunctional value of arable land. The scientific measurement of the integrative value of arable land before and after land consolidation can improve farmers’ overall understanding of the value of arable land, increase their awareness of arable land protection, and encourage them to implement arable land protection policies. Additionally, it can provide a theoretical basis for the formulation of reasonable compensation standards for arable land in various areas of the Manas River Basin and effectively promote the use of the “Shawan model”. In this paper, the sample used for the survey was made up of 380 farmers from 10 villages in three different regions of Shawan City (county-level city). The participatory farmer assessment (PRA) method was used to conduct a detailed investigation of the integration of farmers’ cultivated land, while the landscape pattern index method was used to analyze the intensity of the cultivated land integration pattern. By constructing a measurement system for the integrative value of cultivated land and adding up the economic, pro-ecological, and social values before and after the integration of the cultivated land, estimated using the income reduction method, the equivalent factor method, and the shadow engineering method, we found that the cultivated land in each region of Shawan City (county-level city) was more effectively integrated, the scale of the field expanded, the shape of the patches tended to be more regular, and the field surface more flat. However, the degree of integration varied from region to region, with the degree of integration from the largest to the smallest as follows: oasis agricultural zone > oasis/desert ecological zone > hilly zone. We found that the integration of cultivated land has a significant effect on the integrated value of cultivated land, and the value of cultivated land in different regions showed different degrees of improvement after integration. The cultivated land of villages located in the oasis/desert ecotone showed a significant overall improvement after integration, followed by cultivated land in the oasis agricultural area. The value of cultivated land increased significantly, while the value of cultivated land in the hilly area showed less improvement after integration. The value of cultivated land integration in different regions is related to the intensity of the cultivated land integration, the per capita cultivated land area, the ecosystem biomass, and the crop planting area. The purpose of this paper is to effectively diagnose and promote the “Shawan Model” (land integration), formulate reasonable compensation standards for cultivated land in different regions of the Manas River Basin, and implement cultivated land protection policies. Full article
(This article belongs to the Section Landscape Ecology)
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14 pages, 4876 KB  
Article
Analysis of Ecological and Economic Benefits of Rural Land Integration in the Manas River Basin Oasis
by Na Liao, Xinchen Gu, Yuejian Wang, Hailiang Xu and Zili Fan
Land 2021, 10(5), 451; https://doi.org/10.3390/land10050451 - 23 Apr 2021
Cited by 10 | Viewed by 3088
Abstract
Land consolidation is an effective means of promoting the regularization of fragmented arable land, optimizing the allocation of land resources and improving the environment in farming areas, as well as an important means of increasing the economic returns of farming households, and it [...] Read more.
Land consolidation is an effective means of promoting the regularization of fragmented arable land, optimizing the allocation of land resources and improving the environment in farming areas, as well as an important means of increasing the economic returns of farming households, and it is important to scientifically assess the ecological and economic benefits of agricultural land consolidation. In this study, participatory rural assessment (PRA) was used to investigate, in detail, the meaning, satisfaction and changes in farmland rehabilitation before and after implementation. The accuracy of the remote sensing data was verified through an experiment on the net cultivation coefficient. We used a sample of 447 farmers from nine villages in Manas County to study the differences in plot area, crop unit value, income and irrigation before and after the farmers’ integration. We found that, after the integration of farmland, the cultivated area increased significantly, the crop unit yield increased by at least 42.66%, the average income of farmers increased by a value of RMB 4324/ha and the water savings were all higher than 7.18 m3/ha. At the same time, after the integration of farmland, the number of plots was significantly reduced, the arable land became more regular and the microclimate of the farmland improved significantly. The government and individuals should follow the concept and construction requirements of the “community of life in mountain, water, forest, lake, grass and sand”, consider the economic and ecological benefits of land consolidation, ensure the quality of farmland ecosystems, actively explore new models of land consolidation and stimulate the economic vitality of rural areas. Full article
(This article belongs to the Section Land Socio-Economic and Political Issues)
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23 pages, 5837 KB  
Article
Using Moderate-Resolution Temporal NDVI Profiles for High-Resolution Crop Mapping in Years of Absent Ground Reference Data: A Case Study of Bole and Manas Counties in Xinjiang, China
by Pengyu Hao, Li Wang, Yulin Zhan and Zheng Niu
ISPRS Int. J. Geo-Inf. 2016, 5(5), 67; https://doi.org/10.3390/ijgi5050067 - 16 May 2016
Cited by 38 | Viewed by 6775
Abstract
Most methods used for crop classification rely on the ground-reference data of the same year, which leads to considerable financial and labor cost. In this study, we presented a method that can avoid the requirements of a large number of ground-reference data in [...] Read more.
Most methods used for crop classification rely on the ground-reference data of the same year, which leads to considerable financial and labor cost. In this study, we presented a method that can avoid the requirements of a large number of ground-reference data in the classification year. Firstly, we extracted the Normalized Difference Vegetation Index (NDVI) time series profiles of the dominant crops from MODIS data using the historical ground-reference data in multiple years (2006, 2007, 2009 and 2010). Artificial Antibody Network (ABNet) was then employed to build reference NDVI time series for each crop based on the historical NDVI profiles. Afterwards, images of Landsat and HJ were combined to obtain 30 m image time series with 15-day acquisition frequency in 2011. Next, the reference NDVI time series were transformed to Landsat/HJ NDVI time series using their linear model. Finally, the transformed reference NDVI profiles were used to identify the crop types in 2011 at 30 m spatial resolution. The result showed that the dominant crops could be identified with overall accuracy of 87.13% and 83.48% in Bole and Manas, respectively. In addition, the reference NDVI profiles generated from multiple years could achieve better classification accuracy than that from single year (such as only 2007). This is mainly because the reference knowledge from multiple years contains more growing conditions of the same crop. Generally, this approach showed potential to identify crops without using large number of ground-reference data at 30 m resolution. Full article
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22 pages, 10777 KB  
Article
The Potential of Time Series Merged from Landsat-5 TM and HJ-1 CCD for Crop Classification: A Case Study for Bole and Manas Counties in Xinjiang, China
by Pengyu Hao, Li Wang, Zheng Niu, Abdullah Aablikim, Ni Huang, Shiguang Xu and Fang Chen
Remote Sens. 2014, 6(8), 7610-7631; https://doi.org/10.3390/rs6087610 - 19 Aug 2014
Cited by 53 | Viewed by 7996
Abstract
Time series data capture crop growth dynamics and are some of the most effective data sources for crop mapping. However, a drawback of precise crop classification at medium resolution (30 m) using multi-temporal data is that some images at crucial time periods are [...] Read more.
Time series data capture crop growth dynamics and are some of the most effective data sources for crop mapping. However, a drawback of precise crop classification at medium resolution (30 m) using multi-temporal data is that some images at crucial time periods are absent from a single sensor. In this research, a medium-resolution, 15-day time series was obtained by merging Landsat-5 TM and HJ-1 CCD data (with similar radiometric performances in multi-spectral bands). Subsequently, optimal temporal windows for accurate crop mapping were evaluated using an extension of the Jeffries–Matusita (JM) distance from the merged time series. A support vector machine (SVM) was then used to compare the classification accuracy of the optimal temporal windows and the entire time series. In addition, different training sample sizes (10% to 90% of the entire training sample in 10% increments; five repetitions for each sample size) were used to investigate the stability of optimal temporal windows. The results showed that time series in optimal temporal windows can achieve high classification accuracies. The optimal temporal windows were robust when the training sample size was sufficiently large. However, they were not stable when the sample size was too small (i.e., less than 300) and may shift in different agro-ecosystems, because of different classes. In addition, merged time series had higher temporal resolution and were more likely to comprise the optimal temporal periods than time series from single-sensor data. Therefore, the use of merged time series increased the possibility of precise crop classification. Full article
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15 pages, 337 KB  
Article
Emergy-Based Adjustment of the Agricultural Structure in a Low-Carbon Economy in Manas County of China
by Xiaobin Dong, Yufang Zhang, Weijia Cui, Bin Xun, Baohua Yu, Sergio Ulgiati and Xinshi Zhang
Energies 2011, 4(9), 1428-1442; https://doi.org/10.3390/en4091428 - 21 Sep 2011
Cited by 16 | Viewed by 7760
Abstract
The emergy concept, integrated with a multi-objective linear programming method, was used to model the agricultural structure of Xinjiang Uygur Autonomous Region under the consideration of the need to develop a low-carbon economy. The emergy indices before and after the structural optimization were [...] Read more.
The emergy concept, integrated with a multi-objective linear programming method, was used to model the agricultural structure of Xinjiang Uygur Autonomous Region under the consideration of the need to develop a low-carbon economy. The emergy indices before and after the structural optimization were evaluated. In the reconstructed model, the proportions of agriculture, forestry and artificial grassland should be adjusted from 19:2:1 to 5.2:1:2.5; the Emergy Yield Ratio (1.48) was higher than the average local (0.49) and national levels (0.27); and the Emergy Investment Ratio (11.1) was higher than the current structure (4.93) and that obtained from the 2003 data (0.055) in Xinjiang Uygur Autonomous Region, the Water Emergy Cost (0.055) should be reduced compared to that before the adjustment (0.088). The measurement of all the parameters validated the positive impact of the modeled agricultural structure. The self-sufficiency ratio of the system increased from the original level of 0.106 to 0.432, which indicated a better coupling effect among the subsystems within the whole system. The comparative advantage index between the two systems before and after optimization was approximately 2:1. When the mountain ecosystem service value was considered, excessive animal husbandry led to a 1.41 × 1010 RMB·a−1 indirect economic loss, which was 4.15 times the GDP during the same time period. The functional improvement of the modeled structure supports the plan to “construct a central oasis and protect the surrounding mountains and deserts” to develop a sustainable agricultural system. Conserved natural grassland can make a large contribution to the carbon storage; and therefore, it is wise alternative that promote a low-carbon economic development strategy. Full article
(This article belongs to the Special Issue Low Carbon Transitions Worldwide)
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