Changes In Habitat Quality Research Articles

Linking structure and species richness to support forest biodiversity monitoring at large scales

Key messageAuthors have analyzed the possible correlation between measurements/indicators of forest structure and species richness of many taxonomic or functional groups over three regions of Germany. Results show the potential to use structural attributes as a surrogate for species richness of most of the analyzed taxonomic and functional groups. This information can be transferred to large-scale forest inventories to support biodiversity monitoring.ContextWe are currently facing a dramatic loss in biodiversity worldwide and this initiated many monitoring programs aiming at documenting further trends. However, monitoring species diversity directly is very resource demanding, in particular in highly diverse forest ecosystems.AimsWe investigated whether variables applied in an index of stand structural diversity, which was developed based on forest attributes assessed in the German National Forest Inventory, can be calibrated against richness of forest-dwelling species within a wide range of taxonomic and functional groups.MethodsWe used information on forest structure and species richness that has been comprehensively assessed on 150 forest plots of the German biodiversity exploratories project, comprising a large range of management intensities in three regions. We tested, whether the forest structure index calculated for these forest plots well correlate with the number of species across 29 taxonomic and functional groups, assuming that the structural attributes applied in the index represent their habitat requirements.ResultsThe strength of correlations between the structural variables applied in the index and number of species within taxonomic or functional groups was highly variable. For some groups such as Aves, Formicidae or vascular plants, structural variables had a high explanatory power for species richness across forest types. Species richness in other taxonomic and functional groups (e.g., soil and root-associated fungi) was not explained by individual structural attributes of the index. Results indicate that some taxonomic and functional groups depend on a high structural diversity, whereas others seem to be insensitive to it or even prefer structurally poor stands.ConclusionTherefore, combinations of forest stands with different degrees of structural diversity most likely optimize taxonomic diversity at the landscape level. Our results can support biodiversity monitoring through quantification of forest structure in large-scale forest inventories. Changes in structural variables over inventory periods can indicate changes in habitat quality for individual taxonomic groups and thus points towards national forest inventories being an effective tool to detect unintended effects of changes in forest management on biodiversity.

Effects of nutrient reduction and habitat heterogeneity on benthic macroinvertebrate assemblages in a large shallow eutrophic lake

The Taihu Lake ecosystem has been subjected to numerous anthropogenic stressors during the past decades, leading to substantial changes in nutrient dynamics and habitat quality. For instance, the northwestern lake bays receive large amounts of nutrient-rich wastewater and have frequently experienced algal blooms, while the eastern lake region is still dominated by submersed macrophytes. Such changes in environmental characteristics can greatly impact benthic macroinvertebrate communities. We used a 15-year monitoring data series collected by the Taihu Laboratory for Lake Ecosystem Research to examine the spatial and temporal variations of the benthic invertebrate fauna and evaluate its status and trends. We found that three major communities could be distinguished based on taxonomic group composition and abundance, and these corresponded well with three lake habitat types: algal-dominated, macrophyte-dominated, and open-lake zone. An analysis of temporal trends showed major changes in the macroinvertebrates during the study period, largely driven by a lake-wide and significant decline in the abundance of pollution-tolerant taxa. The spatial and temporal variations of macroinvertebrate communities were mainly explained by nutrients (e.g., total nitrogen and ammonium concentrations) and habitat factors (e.g., sediment substrates and macrophyte biomass) as indicated by Random Forests regression, but the major drivers of macroinvertebrate density differed among the three lake zones at the temporal scale. Moreover, our findings suggest that benthic invertebrates were more sensitive to the improvement of the lake's environmental conditions than the pelagic community was. This study provides insights into the responses of macroinvertebrates to ecological dynamics in lakes and highlights the importance of continued monitoring for tracking long-term changes.

Assessment of Topographic Effect on Habitat Quality in Mountainous Area Using InVEST Model

The topographic differentiation patterns of changes in habitat quality are of great significance for the scientific formulation of environmental protection policies in mountainous areas. Here, the distribution, changing trends, and the effects of the topographic gradient on habitat quality were studied using the InVEST model, the topographic distribution index, and the Mann–Kendall test. The results showed that at p < 0.05 (Z = 1.67), the habitat quality from 2000 to 2020 showed three types of trends (significant decline, non-significant change, and significant increase), accounting for 22.2%, 41.8%, and 36% of the changes, respectively. Because of the livelihood structure of the local residents and geological disasters in high-elevation areas, this terrain was the predominant area showing a significant decline in habitat quality. Thanks to the consolidation of projects for the protection of natural forest resources, the return of farmland to forest, and the implementation of projects for protecting the natural forest, the low-lying topography was the predominant area showing a significant increase in habitat quality. The middle topographic position was the predominant area showing no significant changes in habitat quality. Based on the results of the analysis, ecological management and protection measures for high-, medium-, and low-elevation areas were suggested.

Spatial–Temporal Evolution and Driving Factors of Habitat Quality in Malus sieversii Forest Areas in the Western Tianshan Mountain’s Watersheds

The landscape pattern of Xinjiang’s wild apple forest (Malus sieversii) area has undergone substantial change due to human activity disruption and frequent natural catastrophes. This change has a significant influence on the biodiversity and stability of the ecosystem. This study aimed to evaluate the spatial and temporal evolution in habitat quality and landscape pattern changes to analyze the underlying factors affecting habitat quality in the Malus sieversii forest (MF) area in the Mohe watershed of the western Tianshan Mountains. Here, we applied the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model, using four periods of remote sensing images of 1964, 1980, 2000, and 2017 as data sources, and analyzed the trend of landscape pattern changes in the MF area. The results show that (1) from 1964 to 2017, the study area was greatly affected by anthropogenic disturbance and climate change. Each landscape index indicates that the fragmentation of the whole study area has increased, the stability of the ecosystem has weakened, and the habitat quality is somewhat in jeopardy. (2) Analyzed in terms of spatial and temporal characteristics, the habitat quality of the whole study area decreased from 1964 to 2017. Among them, the low habitat value is mainly distributed in the north and northeast, the central part of the study area shows scattered low-habitat-value areas, and in the high-altitude area in the south, the ecosystem is more stable. (3) Since the northern region is dominated by cultivated land patches and residential building land patches, the habitat quality of the stressed zone deteriorates the larger its maximum patch area. The habitat quality of the region under stress worsens the larger its maximum patch size. In the area dominated by MF, the larger the area of MF patches, the higher the ecological service value. The study may be helpful for comprehending how the dynamics of landscape patterns affect biodiversity. It may also offer a scientific foundation for improving regional natural environments and effective decision-making support for local governments in the areas of landscape design and biodiversity preservation.

Dynamic Changes in Habitat Quality and the Driving Mechanism in the Luoxiao Mountains Area from 1995 to 2020

The strengthening of regional habitat quality is crucial to protect biodiversity and fully utilize ecosystem services such as those provided by forestry and aquatic ecosystems. However, the long-term patterns of change in the habitat quality of the Luoxiao Mountains area, which is both an important ecological barrier area and a concentrated poverty-stricken area, and the driving mechanism remain unclear. In this study, the InVEST model was used to assess the habitat quality of the Luoxiao Mountains area in 1995 to 2020, and the spatial autocorrelation model was used to explore the spatial and temporal variation and distribution characteristics of habitat quality. Further, ordinary least squares (OLS) model, geographically weighted regression (GWR) model, and random forest (RF) algorithm were combined with multidimensional datasets to explore the underlying mechanisms driving changes in habitat quality. According to the results, the habitat quality indices of the Luoxiao Mountains area in 1995, 2005, 2015, and 2020 were 0.822, 0.818, 0.817, and 0.813, respectively, with an overall decreasing trend. The RF model was the best fit for habitat quality, better than the GWR and OLS models. Physical geographic factors such as slope and precipitation, as well as socioeconomic factors such as gross domestic product, were key drivers of habitat quality in the Luoxiao Mountains. Precise implementation of ecological protection and restoration measures, improvements in the efficiency of spatial utilization, and exploration of the value of ecological products are key factors in maintaining a balance between habitat quality and economic growth into the future.

Erratum to “Dynamic Changes in Habitat Quality and the Driving Mechanism in the Luoxiao Mountains Area from 1995 to 2020”

Erratum to “Dynamic Changes in Habitat Quality and the Driving Mechanism in the Luoxiao Mountains Area from 1995 to 2020”

黄土高原农户生计转型及其生态效应——以陕西省佳县为例

PDF HTML阅读 XML下载 导出引用 引用提醒 黄土高原农户生计转型及其生态效应——以陕西省佳县为例 DOI: 10.5846/stxb202203280766 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金(41771574) Farmers' livelihood transition and ecological effects on Loess Plateau: A case study of Jiaxian County, Shaanxi Province Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:在乡村地域系统人地关系日趋复杂的情况下,农户生计活动与生态环境之间的关系已成为生态效应研究的核心。本文以陕西省佳县为研究区,结合遥感影像、GIS技术和实地调研获取的微观数据,对1990年以来典型生态脆弱区农户生计对生态环境的影响进行长时序动态监测和分析,从农户种植结构、收入结构和劳动力要素投入结构对农户生计类型和乡村发展类型进行界定,分析农户生计转型过程和特征,基于土地利用分析生境质量时空变化,以生境质量为媒介分析农户生计转型的生态效应。主要结论如下:(1)佳县农户类型和乡村类型演化特征显著。从农户尺度上看,农户生计类型从以粮食主导型为主,逐渐演化为非农主导型为主粮食主导型为辅的组合模式。从乡村类型上看,传统农业型和新型农业型均逐渐演化为非农业型。(2)农户生计转型路径由多元化逐渐转向单一非农化发展,不同农户生计转型过程存在差异,按照转型路径特征可分为4类:持续稳定型、渐进型、调整型和倒退型。(3)生境退化度呈下降态势,从退化等级上看,无退化、轻度退化和中度退化等级面积增加,高度退化等级面积减少,严重退化等级面积降低为0。生境质量呈波动上升态势,从等级上看,占主导的为优等和较差等级,且优等级占比始终最高。(4)农户生计与生态环境之间的复杂反馈关系处于动态变化之中,且二者之间相互影响。在农户生计非农化转型过程中,生境退化度在逐渐降低,生境质量显著提升,农户生计方式转型主要通过对土地利用、资源消费模式以及生态系统产生作用,进而产生生态效应。 Abstract:With the increasingly complex relationship between people and land in the rural regional system, the relationship between the livelihood activities of farmers and the ecological environment has emerged as the core of ecological effect research. This paper takes Jiaxian County in Shaanxi Province as the research area, combines remote sensing images, GIS technology and microscopic survey data obtained from field research, to conduct long-term monitoring and analysis the impact of farmers' livelihood on the ecological environment in typically ecological fragile areas since 1990. This paper defined the types of farmers based on the planting structure, income structure, and labor input structure of farmers, also defined the type of villages' development. We analyzed the process and characteristics of farmers' livelihood transformation, the temporal and spatial changes in habitat quality based on land use, and used the habitat quality as a medium to analyze ecological effects of farmer' livelihoods transformation. The main conclusions are as follows: (1) the evolution characteristics of the types of farmers and villages in Jiaxian County were significant. The type of farmer households has gradually evolved from a food-dominated type to a non-agricultural-dominated type with the main food-dominated type supplemented. From the perspective of rural type, both traditional agricultural type and new agricultural type have gradually evolved into non-agricultural type. (2) The farmers' livelihood transformation paths in Jiaxian County have gradually shifted from the diversified development to a single non-agricultural development path. Different farmers' livelihood transformation processes are not the same. The transition path can be classified into four types: continuous and stable, gradual, adjustment, and retrograde. (3) The degree of habitat degradation showed a downward trend. In terms of degradation grades, the areas of no degradation, slight degradation, and moderate degradation increased, the area of highly degraded grades decreased, and the area of severely degraded grades decreased to 0. Habitat quality showed a fluctuating upward trend. From the perspective of grades, the dominant grades were excellent and poor grades, and the proportion of excellent grades was always the highest. (4) The complex feedback relationship between farmers' livelihoods and the ecological environment is in dynamic change, there is a mutual influence between the two. During the transition of farmers' livelihood to non-agricultural transformation, the degree of habitat degradation is gradually decreasing, and habitat quality is significantly improving. The transition of farmers' livelihoods mainly produces ecological effects by affecting land use, resource consumption patterns and ecosystems. 参考文献 相似文献 引证文献

西辽河上游生境质量时空演变特征与影响机制

PDF HTML阅读 XML下载 导出引用 引用提醒 西辽河上游生境质量时空演变特征与影响机制 DOI: 10.5846/stxb202112243648 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划（2016YFC0503603） Characteristics of spatio-temporal evolution and influence mechanism of habitat quality in the upper reaches of the West Liaohe River Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:西辽河上游是我国辽河流域的重要水源地，其生境质量的好坏关系到下游流域生态安全和人类福祉。然而针对西辽河上游生境质量及其影响机制的研究还有待深入。基于ArcGIS软件、InVEST模型，定量分析了西辽河上游1980-2018年土地利用和生境质量的时空演变特征；并进一步探究了西辽河上游生境质量变化的主要驱动因子。结果表明：（1）1980-2018年，西辽河上游草地面积较1980年下降了21.93%，其中大部分转化为林地（7719.09 km2）、耕地（6014.90 km2）和裸地等（3025.71 km2）等，各斑块的空间分布异质性增加；尽管研究期内，林地面积较基期大幅度提升了48.67%，但全区域平均生境质量指数由0.74下降到0.72。（2）该地区无论在区域本底环境和区域社会经济发展水平上，均对于西辽河上游的生境质量改善产生了积极作用，年均气温（0.218）、降水（0.229）、地区生产总值（0.850）和受教育程度（0.132）与生境质量指数呈现较为明显的正相关关系；然而，本地区城镇化速率（-1.137）、景观分离度指数（-0.532）和道路的扩张（-0.394）与生境质量指数呈现较为明显的负相关，可见快速的城镇化所引起的人类活动加剧是导致区域生境质量的下降的重要诱因。本研究旨在为平衡区域发展和生态保护，为以半干旱农牧交错带地区为代表的生态脆弱区可持续发展提供科技支撑。 Abstract:The upper reaches of the West Liaohe River is one of the most important water sources of the Liaohe River Basin in China, and the quality of its habitat is directly related to the ecological security and human well-being of the downstream basin. However, the relevant studies on the habitat quality about the upper reaches of the West Liaohe River is still relatively scarce, and further studies on its influencing mechanism also needs to be conducted. Based on the models of ArcGIS and InVEST, our study quantitatively analyze the spatial and temporal evolution characteristics of land use and habitat quality on the upper reaches of the West Liaohe River from 1980 to 2018, what is more, we also further explored the main driving factors which caused the habitat quality changes during the 38 years. Several results have showed that:(1) From 1980 to 2018, the grassland patches area in the upper reaches of the West Liaohe River decreased by 21.93% compared with that in 1980, most of which has been converted into forest (about 7719.09 km2), farmland (about 6014.90 km2) and bareland (about 3025.71 km2). Meanwhile, the spatial heterogeneity of the land use patches in the study area has increased. Although the area of forest land patches increased by 48.67% compared with the that in 1980, the average habitat quality index of the whole area has dropped from 0.74 to 0.72. (2) Over the past 38 years, both the regional background environment and the level of regional social and economic development had played a positive role on the improvement of habitat quality in the upper reaches of the West Liaohe River. The factors, such as the annual average temperature, the precipitation, and the level of education, have shown significantly positively correlated with the habitat quality index, which regression coefficients were described as 0.218, 0.229, 0.850, 0.132 respectively. However, the factors, such as the urbanization rate, the splitting index, and the expansion of urban roads, have showed a negative relationship with the habitat quality index, which regression coefficients were expressed as -1.137, -0.532, and -0.394 respectively. It could be seen that the intensification of human activities caused by the rapid urbanization is an important inducement leading to the deterioration of the regional habitat quality. The study aimed to balance regional development and ecological protection about the upper reaches of the West Liaohe River. Moreover, it aimed to provide scientific and technological support for the sustainable development of ecologically fragile areas represented by semi-arid agro-pastoral ecotone. 参考文献 相似文献 引证文献

Spatiotemporal responses of habitat quality to land use changes in the source area of Pearl River, China.

Habitat quality assessment provides an effective interface for exploring the mechanisms linking land use change and biodiversity. We used InVEST model to assess the spatial and temporal variations of habitat quality in the Pearl River source area from 2000 to 2020, and to examine the impacts of land use change on habitat quality. The results showed that during the study period, construction land had the largest change, with an area increase of 321.48 km2, and the area of grassland decreased most significantly. Habitat quality in the Pearl River source area was generally at a high level, with a small downward trend. The low value areas were concentrated in the town centers and main agricultural production areas, while habitat quality was high in the mountainous areas in the south and north region. The cold spots of habitat quality change had the most significant aggregation effect in the Quzhan Basin along the Nanpan River. The number of hot spots was small and scattered. Among the various types of nature reserves, habitat quality of Jiache Nature Reserve in Huize County was the lowest, and that of Zhujiangyuan Nature Reserve had a slight decreasing trend, mainly due to the transformation of grassland to cropland. The contribution of habitat quality degradation driven by land function change was 5.6 times as that of improvement. The encroachment of urban and rural construction space into grassland ecological space and agricultural production space was the dominant factor driving the reduction of habitat quality in the Pearl River source area. The contribution of construction land expansion decreased from 69.9% (2000-2010) to 46.7% (2010-2020). The expansion of construction land was the main cause for the degradation of habitat quality. The degradation threat from arable land expansion overtook the traffic network construction as the secondary threat source from 2010 to 2020. It was necessary to increase control of nature reserves in the Pearl River source area and to implement land use regulation strictly to guarantee no net loss and integrity of the ecosystem.

Spatio-Temporal Evolution and Influence Mechanism of Habitat Quality in Guilin City, China.

Based on the models of ArcGIS10.5, Fragstats 4.2, and InVEST, this research describes the temporal and spatial evolution characteristics of habitat quality in Guilin from three aspects, which are land use change, landscape pattern change, and habitat quality evaluation, and further explores the main driving factors of Guilin's habitat quality change by using the method of geographic detector evaluation. The results indicate that from 2000 to 2020, the land use type in Guilin City is dominated by forest, accounting for the highest proportion of 77.87%. The forest has decreased significantly, the mutual transformation of forest and cropland is obvious, and the area of impervious has continued to increase. A large amount of cropland is occupied, indicating that human activities were the main factor in land use transformation. From 2000 to 2020, the irregularity of the patch shape of each land use type was deepened, the fragmentation degree was relatively stable, the landscape diversity was enhanced, and the spatial distribution of each patch showed a relatively obvious heterogeneity. From 2000 to 2020, the habitat quality of Guilin City was mainly high-grade and the habitat quality was good, but the overall trend showed a downward trend, and the spatial difference was obvious. From 2000 to 2020, elevation, normalized difference vegetation index (NDVI), splitting index (SPLIT), and slope were the main factors affecting the habitat quality of Guilin City, among which elevation and NDVI had the most significant effects.

Evolution of Habitat Quality and Its Response to Topographic Gradient Effect in a Karst Plateau: A Case Study of the Key Biodiversity Conservation Project Area of Wuling Mountains.

Habitat quality (HQ) is widely considered to be a proxy indicator for biodiversity. Assessing the dynamic changes in HQ induced by land-use and land-cover (LULC) changes could provide a scientific perspective for regional sustainable development, especially in the ecologically fragile karst plateau mountainous areas. We selected nine landscape metrics to examine LULC dynamics in the Key Biodiversity Conservation Project Area of Wuling Mountains in Guizhou province, China, based on the land-use data for the 1990-2018 period. HQ was evaluated using the InVEST model and the topographic gradient effect on HQ was analyzed using the topographic position index. The results showed that the dominant land categories in the study area were arable land, grassland, and forestland. Land transformation was mainly characterized by a shift from cultivated land to construction land and forestland, and a mutual conversion between grassland and forestland. The changes improved landscape heterogeneity and the degree of fragmentation. The HQ of the study area was high, although exhibited a declining trend from 1990 to 2018. The eastern and western parts had relatively high HQ, whereas the southern and northern parts had low HQ. The topographic gradient had a significant effect on spatial patterns of HQ. High HQ distribution was consistent with that of forestland and was dominant along the topographic gradient, while low HQ distribution was consistent with that of construction land and cultivated land and was dominant along the topographic gradient.

Effects of Coastal Urbanization on Habitat Quality: A Case Study in Guangdong-Hong Kong-Macao Greater Bay Area

Coastal areas are usually considered as pioneering areas for economic development and reform due to their unique geographical locations and ecological conditions. Correspondingly, rapid urbanization in coastal urban agglomerations has resulted in population concentration and land use/cover change (LUCC), leading to the decline of habitat quality and biodiversity. However, few studies have quantitatively explored the impacts of urban agglomeration expansion in coastal zones on habitat quality. Taking the Guangdong-Hong Kong-Macao-Great Bay Area (GBA) as a case study, we applied the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model to assess the habitat quality based on land use data obtained from remote sensing images from 1980 to 2020 and developed a geographically weighted regression model to quantitatively analyze the response of habitat quality to urbanization. The results showed that (1) LUCC in the GBA was dramatic from 1980 to 2020, dominated by the shift from various land use types to construction land, which led to increased fragmentation; (2) the overall habitat quality showed a decreasing trend, characterized by low values in the central part and high values in the surrounding area; (3) population and construction land such urbanization elements had a more significantly negative effect on habitat quality changes, while the relationships among slope, road distance, and habitat quality changes were complex. Based on above analysis, this paper suggests that future land management in the GBA should develop in the direction of intensification, refinement, and regional integration.

Estimating the Economic Value of Change in Ecosystem Habitat Quality in South Korea Using an Integrated Environmental and Economic Analysis

Jeju Island is one of the most prominent ecotourism destinations in South Korea and has steadily been the subject of land-use development. In this study, the economic value and benefits of habitat quality changes on Jeju Island were estimated through an integrated environmental and economic analysis linking the unit values of ecosystem services to the physical habitat quality measures predicted by the InVEST Habitat Quality Model. A choice experiment survey was conducted to estimate the willingness-to-pay for the changes in habitat quality at 12 tourist sites using a hybrid econometric model. The results indicate the presence of heterogeneity in respondents’ preferences for ecotourism destinations. Visitors were most sensitive to changes in the habitat quality level among three attributes: on-site facilities, information and interpretation services, and habitat quality. Based on the willingness-to-pay for each tourist site, the total benefit resulting from the improvement of habitat quality in the 12 tourist sites is substantial. The integrated environmental and economic analysis framework used in this study would effectively produce plausible economic values generated by environmental goods and services. The findings also provide a basis for considering the importance of economic benefits provided by ecosystem services in decision-making.

Spatiotemporal change of habitat quality in Hainan Island of China based on changes in land use

Hainan Island has undergone rapid landscape transformation leading to habitat fragmentation.Thus, exploring the spatiotemporal change from its past habitat quality provides insights into its future ecological protection. This study investigated the spatiotemporal changes of the habitat quality of Hainan Island from 1980 to 2020 using the InVEST and CA-Markov models and predicted the habitat quality for the time frame of 2020–2040. We found that the habitat quality index first increased from 0.73 in 1980 to 0.74 in 1990 and then will decrease to 0.70 in 2040 with an accelerating rate. The habitat quality inside the national park was significantly better and more stable than that outside the national park. The simulation and prediction results showed that the habitat quality inside the national park would continue to improve from 2020 to 2040, while that outside the national park would decline. The spatial distribution of the changes in the habitat quality of Hainan Island was significantly autocorrelated and clustered, enhanced over time. Our results suggest that the overall decline in the habitat quality of Hainan Island mainly result from the habitat quality change outside the national park, and the habitat quality change inside the national park will play a key role in stabilizing and supporting the habitat quality of Hainan Island, which highlights the importance of national park conservation.

Spatial and temporal dynamics of Mexican spotted owl habitat in the southwestern US

ContextUnderstanding habitat dynamics is essential for effective conservation as landscapes rapidly change. In a companion paper in this issue, Shirk et al. (2023) introduced an automated habitat monitoring system using Google Earth Engine and applied this framework to develop a dynamic model of Mexican spotted owl (Strix occidentalis lucida) habitat across the southwestern US from 1986 to 2020.ObjectivesWe explored the application of this dynamic model of Mexican spotted owl habitat in the context of the species’ ecology.MethodsWe evaluated environmental correlates of Mexican spotted owl habitat, assessed potential spatial non-stationarity in habitat selection, estimated long-term trends in habitat by quantifying changes in habitat amount and quality between 1986 and 2020, and evaluated the extent to which habitat changes over the past 35 years have been driven by wildfire.ResultsTopography and climate appeared to outweigh reflectance-based (vegetation) metrics in describing Mexican spotted owl habitat and habitat selection was non-stationary across modeling sub-regions. Total habitat area for Mexican spotted owls declined by ~ 21% since 1986 (0.6% annually), but trends varied spatially and some even reversed over the past decade. Wildfire was responsible for between 8 and 35% of total habitat loss, depending on the sub-region considered.ConclusionsThe automated habitat monitoring system allowed trend estimation and accurate assessment of current habitat status for Mexican spotted owls; maps were accurate, spatially detailed, and current. The ability to continually produce accurate maps for large land areas for threatened species such as the Mexican spotted owl facilitates science-based land management on public lands in the southwestern US.

Habitat quality assessment of wintering migratory birds in Poyang Lake National Nature Reserve based on InVEST model.

Poyang Lake National Nature Reserve (PLNNR) is an important resting place for wintering migratory birds on the East Asian-Australasian Flyway (EAAF). In recent years, due to human activities and climate change, the area of wetlands has shown a downward trend, and the number and habitat of wintering migratory birds have been threatened. It is urgent to evaluate the habitat quality of wintering migratory birds in PLNNR. Therefore, the InVEST model and landscape index were used to evaluate the habitat quality of wintering migratory birds, and the grey correlation theory was used to reveal the response of typical wintering migratory bird population to habitat quality. The results showed that the habitat quality of the PLNNR was still at a high level, but showed a downward trend, with the average index of habitat quality decreasing from 0.872 to 0.817. The area of the highest quality habitat decreased by 3394.92 hm2, the area of the lowest, low, and medium quality habitats increased by 3112.11 hm2, and the area of the high quality habitat remained stable. The lowest, low, and medium quality habitat expanded from the middle to the south of the PLNNR mainly because of the expansion of construction land and cultivated land. The area with deterioration in habitat quality was 10,477.53 hm2, mainly concentrated in the center and south of the PLNNR. The area with restoration in habitat quality was 6148.26 hm2, mainly concentrated in the Bang Lake and Dacha Lake. The area with no change in habitat quality remained stable. The fragmentation degree and shape complexity of highest and high quality habitats increased, dominance degree and connectivity decreased, and the landscape pattern of habitat quality showed a downward trend. Typical wintering migratory birds have a strong correlation with highest, high, and low habitat quality, and there is a downward trend with the deterioration of habitat quality. Finally, this paper puts forward constructive suggestions on the degradation of habitat quality caused by land-use change.

Simulation of Land Use Change and Habitat Quality in the Yellow River Basin under Multiple Scenarios

Habitat quality is the key to regional ecological restoration and green development, and land use change is an essential factor affecting habitat quality. Studying the spatial and temporal evolution characteristics of land use change and habitat quality under multiple scenarios is significant for regional ecological restoration and management, and for preventing future ecological and environmental risks. We used the improved Logistic-CA-Markov (Logistic-Cellular Automata-Markov) and InVEST (Integrated Valuation of Ecosystem Services and Trade-offs) models to establish the spatial patterns of habitat quality in the Yellow River Basin from 2000 to 2040 and analyzed the characteristics of land use and habitat quality changes under scenarios of natural development (S1), ecological protection (S2), and urban expansion (S3). The results showed that in 2000, 2005, 2010, 2015, and 2020, the main land use types in the watershed were dryland and grassland, accounting for more than 72%. Paddy land, dryland, woodland, middle-coverage grassland, and unused land all showed decreasing trends, whereas all other land types showed increasing trends. Influenced by human activities and the environment, the watershed habitat quality was low, with 80% of the areas with middle to low grades, but the overall trend was rising. The spatial variability in habitat quality of the watershed was significant, with habitat quality improvements in the central and northern regions and continued deterioration around the cities in the southern and western parts. The spatial autocorrelation and aggregation of habitat quality in the watershed were strong, and future land use patterns in the study area had a significant relationship with human activities. Simulation of future scenarios revealed ecological conservation catalytic effects on habitat quality in the study area, whereas urban expansion deteriorated watershed habitat quality. This study could provide support for future ecological conservation decisions.

Habitat quality assessment provides indicators for socio-ecological management: a case study of the Chinese Loess Plateau.

The impact of changing land use and land cover (LULC) on regional habitat quality have attracted extensive attention. The Loess Plateau is an ecologically fragile area; LULC changes in this region have complex impacts on habitat quality at multiple spatiotemporal scales. This study developed an integrated assessment method based on multi-source data to assess habitat quality changes in the Loess Plateau during recent years (2000-2015) and in the future (2015-2050) under four typical scenarios. A significant increase in urban land use was observed on the Loess Plateau from 2000 to 2050, which resulted in a continuous decrease in the cropland area. The area of forest and grassland landscapes was also reduced by both urban and cropland expansion, with the most significant loss in the grasslands. A future overall decreasing trend in overall habitat quality is predicted, but the SSP1-2.6 scenario is significantly better than the SSP5-8.5 scenario. Urban expansion contributes a rapidly increasing proportion of habitat quality decline on the Loess Plateau; urban land will become the most significant threat to regional habitat quality by 2030. Policies for socio-ecological protection with clear, high-level objectives can effectively promote habitat quality. It is recommended that national nature reserves be delineated and ecological functions in the study area be continuously monitored. This research provides a potential socio-ecological baseline and implementation strategy for the habitat conservation-oriented management of large and fragile ecological regions.

Direct and Spillover Effects of Urban Land Expansion on Habitat Quality in Chengdu-Chongqing Urban Agglomeration

Urban land expansion has dramatically changed the spatial distribution patterns and functional structure of habitats. Previous studies on the spatial externality effect of urban land expansion on the habitat quality of urban agglomerations are still insufficient. With the use of remote sensing and statistical data from 2000 to 2018, this study explored the evolutionary relationship between urban land expansion and habitat quality in the Chengdu-Chongqing urban agglomeration (CUA) using the bivariate local autocorrelation method and spatial Durbin model. Partial differential equation decomposition of the local and spatial spillover effects was implemented to investigate the marginal effects of the influencing factors. The highlights of the results are as follows: CUA’s urban land increased by 2890.42 km2 from 2000 to 2018, mainly caused by urban encroachment over farmland and grassland. New urban lands were situated primarily in the main urban districts of Chengdu and Chongqing; urban expansion intensity slowed to 7.64% in 2010–2018, declining by 53.95% from 2000 to 2010. The average habitat quality decreased to 0.905, and two “ring-shaped decline areas” were formed around the main urban areas of Chengdu and Chongqing. “Low-High” and “Low-Low” clusters were the main associations between urban land expansion and habitat quality changes. The impact of urban land expansion on local habitat quality changed from insignificant to negative, while its spatial spillover effects over adjacent areas have increased the negative environmental externalities to habitat quality in adjacent areas through spatial spillovers. Our findings provide evidence for urban agglomerations such as CUA that are still being cultivated to carry out cross-city joint protection strategies of habitat quality, also proving that habitat quality protection should be an integration of urban expansion regulation, natural adaptation and socioeconomic adjustment.

In-river weir effects on the alteration of flow regime and regarding structural stream habitat

In-river hydraulic structures may negatively impact aquatic ecosystems, including changing river flow regimes and the habitat quality of endemic fish habitats. This study integrates the wavelet analysis and the time-series exceedance probability method to quantify the degree of evolution in the river flow regime caused by weirs and determine the critical time scale most affected in the environmental flow. Hydrodynamic and habitat models were conducted to analyze the influence of the variant flow characteristics between the dry and wet seasons on the habitat structure. Four endemic fishes were selected as the indicator species to represent different habitat preferences and reveal the spatiotemporal changes in habitat quality. The flow difference between dry and wet seasons became more extensive after the weir construction, indicating the alternative flow regime downstream. The annual deviation of daily flow dramatically raised, showing the flow rates decline in the dry season and enlarge in the wet season. The findings exhibit that the downstream flow amplitude changes regardless of time scale after constructing the weir. The flow data from the 2-days scale to the 1-week scale were most adjusted, meaning that these periods to meet the environmental flow decline significantly. The critical environmental flow corresponding to lower flow events was apparently influenced in the dry season, in which the Q75 and Q90 displayed the highest degradation in fish habitat quality. In addition, the simulation results of the habitat model found that glide is the primary habitat type. The total water area and the habitat diversity were reduced, while the habitat quality also had a lowered tendency after the weir operation. The habitat run was most degraded, and the riffle was also significantly negatively impacted. Regarding the endemic fish species,F. lacustresuffered the most harmful effects on suitable-habitat quality and quantity from the weir. This study suggests considering natural flow regimes at the planning and design phases of weir construction and rehabilitating these essential habitat patterns to mitigate the downstream ecosystem impacts.